This report is made available here for information only. It was compiled by Rich Stowell.

Piper Tomahawk PA-38-112 --
Dangerously Unpredictable or Misunderstood Trainer?



REPORT CHRONOLOGY
June 4, 1997 -- report first posted, sub-titled "-38-112 -- Worth Dying In?"
June 14, 1997 -- added my letter to Phil Boyer/President, AOPA
June 21, 1997 -- added reference to and info from The Aviation Consumer
June 24, 1997 -- added responses from Phil Boyer/AOPA and Bruce Landsberg/AOPA ASF
July 8, 1997 -- added my analysis of AOPA's Safety Review and response to Bruce Landsberg,
improved Report format and text
July 13, 1997 -- added text of 7-page letter from NTSB to FAA dated July 10, 1997
December 27, 1998 -- added the McCabe Report

 

Read the Mccabe Report!



Letter from NTSB to FAA -- A 7-page BOMBSHELL! Dated July 10, 1997.
 
Foreword Reference Articles Analysis of AOPA ASF Safety Review
Aviation Consumer Report Correspondence Lowery Press Release
Attachment A -- Piper Report FT-118 Attachment B -- Letter to NTSB OZAEROS HOME


FOREWORD

The following is provided to keep pilots informed of ongoing developments relative to the Piper Tomahawk controversy. Although I have not flown a Tomahawk, based on the number of still unanswered questions regarding stall/spin characteristics that may not be in compliance with the standards for Part 23 airplanes, as well as information provided by pilots whose opinions I respect, it seems prudent for anyone contemplating flying this airplane to proceed with caution.

One well-known flight instructor (with over 7000-plus spins in dozens of aircraft, including the Tomahawk and the Beech Skipper) intimated in a recent phone coversation that of all the airplanes he'd spun over the years, only the Tomahawk gave him an " feeling" about its spin and recovery characteristics.

A test pilot noted that he's witnessed the "" wing of one Tomahawk oil can quite severely at the stall -- the outer half of the wing skins were covered with "" as much as an inch in depth! He also experienced the degradation of another Tomahawk's spin characteristics over the period of a couple of years: from benign spin and recovery characteristics to flat spinning tendencies appearing after just 2-3 turns, requiring another 2-3 turns to recover!

Award-winning instructor, author, and aerobatic pilot Fred DeLacerda -- who has over 300 hours of instruction given in the Tomahawk, including over 200 spins -- was asked, " that the Tomahawk was designed, marketed, and sold as an airplane approved for up to 6-turn spins, and given your experience in the airplane, do you consider the Tomahawk a suitable spin training platform?" Mr. DeLacerda responded emphatically, "!"

Dr. Kroeger -- the primary designer of both the Tomahawk and the Beech Skipper -- designed two strikingly similar airplanes: Both have T-tails and O-235 Lycoming engines. Both use the GAW-1 airfoil, have bubble canopies, are comparably sized, and have max. gross weights of 1,670 and 1,675 pounds respectively. Both have very similar mission profiles and are targeted for the same piece of the aviation market.

Does it make sense then that the two airplanes should exhibit stall/spin characteristics sufficiently different enough BY DESIGN so that pilots would be twice as likely to die from an inadvertent stall/spin in one (the Tomahawk) versus the other (the Skipper)? Or is there credence to the allegation that the changes made to the Kroeger-designed (original prototype) Tomahawk resulted in production airplanes that may display unpredictable stall/spin characteristics, failing to conform to the standards for Part 23 airplanes in the process?

Use the following to help you assess the level of personal risk and to help you form your own opinion on the matter. Personally, I will not spin, much less fly a Tomahawk until this issue has been resolved, and all of the questions asked have been answered satisfactorily.

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REFERENCE ARTICLES

Aviation Safety, February 1, 1996, " on Trial", by John Lowery

Aviation Safety, October 15, 1996, " Tomahawk Spins In", by John Lowery

AOPA ASF CFI Checklist, Fall 1996, ": To Spin..."

Aviation Safety, June 1997, " Not Closed on PA-38", by John Lowery

The Aviation Consumer, December 1/15, 1990, " PA-38 Tomahawk"

AOPA ASF " Review: Piper Tomahawk PA-38-112," 1996

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ANALYSIS OF AOPA ASF SAFETY REVIEW

July 7, 1997

Mr. Bruce Landsberg, Executive Director
AOPA ASF
421 Aviation Way
Frederick, Maryland 21701

Re: Tomahawk Safety Issues

Dear Bruce:

Thank you so much for responding to my June 10 letter, and for sending the copy of the ASF publication, " Review -- Piper Tomahawk PA-38-112". I've read the point-by-point responses to my questions and the pertinent information in the Safety Review. I still have some lingering questions, however, that I hope the Air Safety Foundation will address:

It appears ASF's assertion that the Tomahawk exhibits acceptable stall/spin behavior, and therefore that it is a suitable spin training platform, is based on the following hypothesis:

The Tomahawk was intentionally designed to behave significantly different from its direct competitors (C-150/152, BE-77), and it is incumbent upon pilots and CFI's to understand its nature.

To lend support to the " differences in stall/spin behavior" hypothesis, the Tomahawk Safety Review and subsequent AOPA articles rely primarily on specific information found in manufacturer-approved POH's.

Following is a two-part analysis of the same information from another perspective. Part I deals with the purported evidence of " differences" found in manufacturer literature regarding stalls and spins; Part II deals with anecdotal evidence of " differences" observed in actual stall/spin flight operations.

PART I -- Analysis of Published Information

1. Tomahawk Safety Review, Page VII, Third Par., quoting from an FAA letter to the ASF:

"The Type Certificate was issued on December 20, 1977; there were two airplanes used for the certification flight tests, S/N 38-78A001 (N38PA) and S/N 3878A002 (N381PT) .... The certification flight test report, 'Flight Test Report FT-118,' was completed on December 16, 1977."

These statements seem to imply that FT-118 chronicles the certification flight tests using N38PA and N381PT; yet neither John Lowery's copy of FT-118, nor the pages of the report in my possession mention either of these two airplanes. The only airplane I can find referenced in flight test report FT-118 is the T-tail version of the first (experimental) prototype, N56346.

QUESTION: Is there an addendum or revision to FT-118 that Mr. Lowery's copy may be missing, or a different flight test report altogether that specifically identifies airplanes N38PA and N381PT as used for the certification flight tests? If so, will the ASF furnish copies of the missing document(s)?

2. Tomahawk Safety Review, Page VII, Ninth Par.:

"as operational experience is gained, the relationship between pilot and plane grows. Pilots develop their own procedures and techniques to either accommodate or overcome the airplane's design or handling characteristics."

If possible, please clarify this statement as it relates to learning about the Tomahawk's stall/spin behavior through a study of the approved POH versus learning about it through actual experience.

I'm sure the ASF does not mean to imply that it is generally acceptable practice for pilots to find ways to "" -- defeat, short circuit, circumvent -- inherent design properties to suit their own needs. (For example, it would not be acceptable for a pilot of a hypothetical airplane that is not approved for intentional spins to try to overcome its inherent spin resistance in order to do spins.)

Also, the conclusions reached in the ASF Safety Review and subsequent Tomahawk articles in AOPA Pilot and CFI Checklist are defended using information published by the airplane manufacturers, not on any so-called pilot-developed -- "" -- procedures and techniques.

The accompanying ASF letter to me further noted, "ASF chose to use the Pilot's Operating Handbook for the PA38..." as the primary source supporting its " differences" hypothesis.

3. Tomahawk Safety Review, Page VIII, Last Par.:

"The Tomahawk has significantly different stall and spin characteristics, by design, from other comparable aircraft."

Referencing item #1 above, the flight test report FT-118 for the prototype N56346 clearly indicates otherwise: "Spin entry and recovery is conventional..."

As noted in #2 above, ASF's accompanying letter stated, "ASF chose to use the Pilot's Operating Handbook for the PA38 ... and not the Piper report FT-118 that you [Rich Stowell] cite. The POH is ... more conservative in every case than FT-118..."

It may be true that the POH is more conservative than the flight test report; however, it does not follow that it would be " conservative" to label as significantly different stall/spin behavior identified as conventional in the flight test report.

Furthermore, the term " different" does not appear in the stall or spin sections of the Tomahawk POH. Nothing in the text of " 4: Normal Procedures, 4.35 Stalls," for instance, would lead a pilot or instructor to expect the Tomahawk's stall characteristics to be any "" from comparable airplanes (see p. 3-32 of the Safety Review).

4. Tomahawk Safety Review, Page 1-7, Second Par.:

"Both Cessna aircraft [C-150/152] recover within 1/4 to 1/2 turn of spin recovery application. The PA-38 may require up to 1-1/2 turns."

Similarly, the Fall 1996 ASF publication, " Checklist" implies: "in a one-turn spin .... the Cessnas should recover within one-quarter to one-half turn following application of spin recovery inputs, the Tomahawk may require up to 1.5 turns."

Interpreted as written, these statements are misleading in that they indicate that the Tomahawk should normally be expected to take significantly longer to recover from spins than its Cessna counterparts. An examination of the manufacturer-published information, however, paints an altogether different picture:

Page 3-32, Second Col., Last Par., quoting from the Tomahawk POH: "Normal recoveries may take up to 1-1/2 turns when proper technique is used...."

Page 3-34, Second Col., Par. 3 & 4, quoting from the C-152 POH: "Up to 2 turns .... Application of recovery controls will produce prompt recoveries of from 1/4 to 1/2 of a turn. If the spin is continued beyond the 2- to 3-turn range .... [recoveries] may take up to a full turn or more. [emphasis added]" Similar wording also appears in Cessna bulletin D5014-2-13-CES-1700-12/81, " Characteristics of Cessna Models 150, A150, 152, A152, 172, R172 & 177", pp. 7-8.

Cessna clearly provides more detailed information on turns-for-recovery than does Piper. Scrutiny of each manufacturers' descriptive text, though, fails to disclose so-called " differences" with respect to the maximum number of turns a pilot or instructor might expect before recovery in either the C-150, C-152, or the Tomahawk:

Note Piper's choice of words: may take up to 1-1/2 turns -- not " take exactly 1-1/2 turns." The manufacturer states that the maximum number of turns for recovery from a worst case spin scenario is 1-1/2. But it could also take LESS than the stated number of turns depending on several factors (number of turns in the spin, a/c weight, c.g., etc.).

Now note Cessna's choice of words for worst case spins of 2- to 3- turns or more: may take up to a full turn or more. For an airplane conforming to the requirements for aircraft approved for intentional spins, " more" can only logically mean " to, but not to exceed 1-1/2 turns." In other words, Cessna has indicated in the POH that the pilot might expect the C-152 to take as many as 1-1/2 turns to recover in some cases; fewer turns in other cases. Again, we are not talking yet about "" differences, only those differences purportedly listed in the POH's.

Based on a careful reading of manufacturer-supplied information in the POH's, it does not seem reasonable to conclude that a pilot should necessarily expect a " difference" in the number of turns for recovery between the Tomahawk and the C-152. In fact, the POH's have more in common than not on this particular point.

5. Tomahawk Safety Review, Page 1-7, Third and Fifth Par.:

"the PA-38 is less docile in a spin than the Cessna 150/152 series .... We suspect that in many accident cases, pilots and instructors familiar with other trainers expected the Tomahawk to behave in a similar fashion. It does not."

Pilots and instructors comparing stall/spin information in the approved Tomahawk POH with the other familiar trainers will find nothing in the Tomahawk text under " 4: Normal Procedures, 4.35 Stalls" (see Safety Review p. 3-32) that would lead them to expect the Tomahawk's stall characteristics to be any "" from other familiar trainers.

Pilots comparing the POH spin entry procedures see that the Tomahawk and Cessna 152 descriptions are quite similar. It is the POH procedure for the Beech Skipper that jumps out as unorthodox to pilots familiar with other trainers -- "The [Skipper's] nose will drop and rotate toward the applied rudder. When the wings are 90 degrees to the horizon, apply full aileron against (i.e.: against the intended direction of spin). The airplane will go slightly inverted and enter a normal spin."

The Tomahawk and C-152 POH's both warn of the importance of maintaining neutral ailerons during spins:

Tomahawk: "The ailerons must remain neutral throughout the spin and recovery because aileron application may alter spin characteristics..."
Cessna 152: "Careful attention should be taken to assure that the aileron control is neutral during all phases of the spin because any aileron deflection in the direction of the spin may alter the spin characteristics..."

Again, it is the Beech POH that stands out as "", prescribing full aileron against the spin direction as a matter of spin entry procedure.

Pilots comparing the published spin recovery procedure for the Tomahawk and the C-152 find strikingly similar verbiage (see Safety Review pp. 3-32 & 3-34/35):

Tomahawk: "Apply and maintain full rudder opposite the direction of rotation."
Cessna 152: "Apply and hold full rudder opposite to the direction of rotation."

Tomahawk: "As the rudder hits the stop, rapidly move the control wheel full forward and be ready to relax the forward pressure as the stall is broken."
Cessna 152: "Just after the rudder reaches the stop, move the control wheel briskly forward far enough to break the stall. Full down elevator may be required..."

Pilots reading the Tomahawk POH find the following additional information regarding the elevator recovery action: "In all spin recoveries, the control column should be moved forward briskly, continuing to the forward stop if necessary [and several paragraphs later] In most cases, spin recovery will occur before the control wheel reaches the fully forward position."

Elaborating on the prescribed elevator action during recovery, the Tomahawk and Cessna POH's describe the input alternatively as "," "". Both POH's state that full forward elevator may be required for recovery in some cases; in other cases, less than full forward elevator will break the stall and complete the recovery.

As noted in item #4 above, nothing in the text of the Tomahawk POH would necessarily lead the pilot or instructor to expect any " differences" in the number of turns required for recovery in the Tomahawk versus the Cessna 150/152. In fact, the POH's have more in common than not on this particular point -- under worst case spin conditions, the Tomahawk, Cessna 150, and Cessna 152 might be expected to take as many as 1-1/2 additional turns for recovery, and all three airplanes may require full forward elevator application during recovery.

6. Tomahawk Safety Review, Page 3-33, First Col, Fourth Par., quoting from the Tomahawk POH:

"The immediate effect of applying normal recovery controls may be an appreciable steepening of the nose-down attitude and an increase in rate of spin rotation. This characteristic indicates that the aircraft is recovering from the spin..."

The accompanying ASF letter to me quoted this same information as well, adding "Those characteristics are not described in either the C150/152 or the Skipper's POH."

Just because this information appears in the Tomahawk POH and not in the C-152 or Skipper POH's does not necessarily mean that the "" characteristic described is peculiar to the Tomahawk. It may simply mean that Piper has provided more detailed information than Cessna or Beech on this particular aspect.

In fact, pilots and instructors well versed in spins and spin dynamics would not be surprised at all to see a momentary increase in the spin's rate of rotation as part of the normal recovery process, especially from developed or aggravated spins.

Not only is the elevator's accelerating effect pointed out and even demonstrated to students by experienced spin instructors, it is also chronicled in several popular textbooks, a few of which follow:

", Spins, and Safety" by Sammy Mason, pp. 86-87 & 106.
" Flight Instructor's Manual" by Bill Kershner, pp. 232-241.
" Basic Aerobatic Manual" by Bill Kershner, pp. 32-36.
" Maneuver Training" by Rich Stowell, pp. 112-118.

Piper's mention of this phenomenon in the POH appears to be merely an inclusion of more detail about generally-observed spin dynamics rather than Tomahawk-specific behavior. Reading such information would not, in and of itself, alert a spin-experienced instructor or pilot about behavior that could be considered " different" from other spinning airplanes.

7. Conclusion:

Nothing in the text of the manufacturer-approved Tomahawk POH would necessarily lead a pilot or instructor to expect the Tomahawk's stall/spin behavior to be " different" from the stall/spin behavior of other comparable airplanes. In fact, the text of the Tomahawk POH actually leads the reader to the conclusion that the Tomahawk should behave the same as other spinnable trainers.

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PART II -- Analysis of Operational (Anecdotal) Information

1. AOPA ASF letter to me dated June 24, 1997:

"Many would agree that the Tomahawk's characteristics in the spin are different from the most common training aircraft .... Pilots agree that the PA38 spin characteristics are different from other training airplanes..."

Piper's FT-118 (using N56346) makes no mention whatsoever of anything other than conventional spin and recovery characteristics for the experimental prototype Tomahawk. The assertion has also been made by AOPA ASF that the POH is in every case " conservative" than the flight test report; however, as the analysis of the POH information in Part I above reveals, nothing in the text of the manufacturer-approved Tomahawk POH would necessarily lead a pilot or instructor to expect the Tomahawk's stall/spin behavior to be "" from the stall/spin behavior of other comparable airplanes. In fact, the text of the Tomahawk POH leads the reader to the conclusion that the Tomahawk should behave the same as other spinnable trainers.

QUESTION: Why does the Tomahawk in flight display behavior so markedly different from the behavior described in FT-118 and in the Tomahawk POH?

2. AOPA ASF letter to me dated June 24, 1997:

"At ASF we are fortunate enough to have a staff member who has several hundred hours in the Tomahawk as a CFI and has conducted many spins with his students."

An unsettling aspect of this issue is the strong division of opinion from equally-qualified pilots and instructors as to the Tomahawk's suitability as a safe, reliable, predictable stall/spin training platform. It seems that for each CFI found to defend the airplane's stall/spin behavior, another can be found with a strongly opposing viewpoint.

For example, how about the well-known instructor (with over 7000-plus spins in dozens of aircraft, including the Tomahawk and the Skipper) who intimated in a phone conversation that of all the airplanes he'd spun over the years, only the Tomahawk gave him an " feeling" about its spin and recovery characteristics?

Or how about the FAA-DER (test pilot) who noted that he's witnessed the "" wing of one Tomahawk oil can so severely at the stall that the outer half of the wing skins were covered with "" as much as an inch in depth? The same test pilot witnessed the degradation of the spin characteristics of another Tomahawk: over the period of a couple of years, it steadily decayed from benign spin and recovery characteristics to flat spinning tendencies appearing after just 2-3 turns, requiring another 2-3 turns to recover.

Or the experiences of those noted in Mr. Lowery's various articles?

Neither the Cessna 150/152 nor the Skipper have such a division of qualified expertise diametrically opposed to their use as stall/spin training platforms.

3. AOPA ASF letter to me dated June 24, 1997:

Regarding John Lowery's contention that the Tomahawk does not meet the certification requirements, the ASF has "not found any information in our research to support his contention".

Referring to item #2 above, any airplane that displays flat spinning characteristics after just 2-3 turns in a spin, requiring another 2-3 turns in which to recover, has failed to meet the certification standard for airplanes approved for intentional spins.

Sometime after the publication of the Fall 1996 " Checklist," AOPA received a letter from Fred DeLacerda -- a noted spin training instructor, accomplished aerobatic pilot, and author of the book " Spins" and many human factors articles -- regarding superficial and potentially misleading information appearing in that article. Mr. DeLacerda's experience includes over 300 hours of instruction given in the Tomahawk, with over 200 spins performed.

Mr. DeLacerda weaves his own experience flying the Tomahawk into his book, " Spins" (Iowa State University Press, 1989, pp. 100-103) as part of a Tomahawk spin accident analysis. His words are revealing:

"There is ample buffet to warn of an approaching stall, but the stall itself is abrupt with no two [Tomahawks] having the same stall pattern. At stall, there is a quick roll-off in one direction or the other .... This loss of lateral control is surprising based on the wing planform .... the skin has considerable flex or 'oil canning' that changes the curvature of the wing. This 'oil canning' is evident during flight .... the resulting asymmetrical lift produces an inconsistent roll-off at stall. Not only is the roll direction unpredictable, but the degree of roll varies from 30 degrees to as much as 90 degrees. [emphasis added]"

The stall behavior described above does not conform to the certification standard for Part 23 airplanes!

He then writes, "The addition of stall strips (two sets) was intended to counter the abrupt stall conditions and roll characteristics, but the effectiveness has been questionable. The roll at stall is still unpredictable. With the abrupt stall and unpredictable high degree roll, the Tomahawk will quickly enter an inadvertent spin. [emphasis added]"

Regarding the number of turns required for spin recovery, Mr. DeLacerda notes, "Recovery requires up to two turns. [emphasis added]"

The spin behavior described above does not conform to the certification standard for Part 23 airplanes!

The stall/spin behavior noted in Mr. DeLacerda's book is not an isolated case. Many qualified pilots have noted similarly non-conforming behavior in the Tomahawk.

Commenting on the spin qualifications of flight instructors, Mr. DeLacerda adds:

"the flight instructor applicant may have never been beyond a one-turn spin and this may have been endorsed by his instructor -- who [likely] had never been beyond a one-turn spin [either]. It is possible for an instructor to have considerable experience in the mechanism of spin entry and one-turn recovery and yet have only a basic understanding of what is actually happening to the airplane and the pilot during entry and recovery. In the multiturn spin, instructor expertise is usually less than marginal at best."

The following question was posed to Mr. DeLacerda in a recent phone conversation:

" that the Tomahawk was designed, marketed, and sold as an airplane approved for up to 6-turn spins, and given your experience in the airplane, do you consider the Tomahawk a suitable spin training platform?"

To which Mr. DeLacerda answered emphatically, "NO!"

4. AOPA ASF letter to me dated June 24, 1997:

Regarding " differences" between the Tomahawk and its like-mission rivals, the C-152 and Skipper, ASF offered the following analogy: "the Piper Aztec and the Aerostar are both certificated under the same rule (identical missions) and have vastly different characteristics."

Comparing the Aztec and the Aerostar because they're "" is not valid, just as it would not be valid to compare the Cessna A152 Aerobat with either the Pitts S-2B or Extra 300 simply because they're "" -- these airplanes clearly are not designed for the same mission profile, invalidating the comparison.

5. Conclusion:

Sufficient anecdotal evidence exists from enough qualified sources to raise serious questions about the stall/spin behavior of the Tomahawk: lack of information in the POH alerting pilots of the potential for unusual or "" differences in stall/spin behavior; wide variations in stall/spin behavior observed by qualified pilots that ranges from "" to "" to stall/spin recovery characteristics clearly outside the conformity parameters established for Part 23 airplanes.

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Final Thoughts

The lack of supporting information in Piper's flight test report and the Tomahawk POH that distinguishes its stalls/spin characteristics as "," significantly or otherwise, from other trainers;

COUPLED WITH

Reports from qualified sources of unpredictable stall/spin behavior;

COUPLED WITH

Reports of uncommanded flat spinning tendencies;

COUPLED WITH

Uncontrollable/unpredictable oil canning/deformation of the wing surface observed at stall;

COUPLED WITH

A higher stall/spin accident rate per 100,000 hrs flown compared to the C-152 (1.7:1) and the Skipper (2.0:1);

COUPLED WITH

Lack of evidence in FT-118 that production prototypes N38PA and N381PT (both highly modified from the experimental prototype N56346) were spin checked for conformity;

COUPLED WITH

Aviation Consumer's claim of " quality control"

COUPLED WITH

The similarities between the Skipper and Tomahawk (size, configuration, wing) except for the reputation regarding stall/spin behavior;

Still leads me to the conclusion that something is amiss regarding the Tomahawk's stall/spin characteristics. I urge the AOPA ASF to reconsider its previous recommendations on this matter and also to reopen its investigation into the stall/spin safety of this airplane.

In the interest of safety,

Rich Stowell
AOPA 863347-3

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THE AVIATION CONSUMER

In its December 1/15, 1990, " PA-38 Tomahawk" report, The Aviation Consumer wrote:

The Tomahawk "was startlingly similar to a Beech design--the PD-285, which had been languishing in development for some years and finally went into production as the BE-77 Skipper .... It seemed more than a coincidence that both airplanes were bubble-canopy, T-tailed, two-door trainers with Lycoming O-235 engines." How similar are the designs? Have a look:

		Tomahawk	Skipper
------------------------------------------
Max. Gross Wt.	1670 lbs.	1675 lbs.
Airfoil		GA(W)-1		GA(W)-1
Lyc. Engine	O-235-L2C	O-235-L2C
Prop. Dia.	72 in.		72 in.
Config.		T-tail		T-tail
Wingspan	34 ft.		30 ft.
Length		22+ ft.		24 ft.
Height		~9 ft.		~8 ft.

While these parameters do not, in and of themselves, guarantee docile stall/spin characteristics, neither do they point to obvious reasons why one aircraft should have at least TWICE the probability of being involved in fatal stall/spin accidents than the other due to a so called "-traditional" design.

The Aviation Consumer went on to report: "At first glance, a Tomahawk can look like a poorly crafted copy of a Skipper."

And later, "The PA-38 prototype showed no evidence of stall strips.... Later models had an additional set of stall strips at the inboard leading edges. All this was meant to correct a tendency for Tomahawks to snap sharply in a stall, sometimes putting even seasoned instructors into unexpected spins. NTSB eventually called for stall strips at all four positions on all Tomahawks, and FAA agreed, making it an Airworthiness Directive. But the Tomahawk still has some unsettling spin characteristics."

And still later, "The vaunted advantage of a T-tail is in spin recovery.... [But then] there is the ferocious waggling of the tail in the stall..."

In conclusion, The Aviation Consumer states, "Other than the evidently poor quality control, our major caveats about the Tomahawk concern its stall/spin behavior..."

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CORRESPONDENCE

June 24, 1997 -- Letter from Phil Boyer, President, AOPA, responding to Rich Stowell

Dear Mr. Stowell,

Thank you for taking the time to document your specific concerns with regard to the Safety Pilot column that appeared in AOPA PILOT magazine on the Piper Tomahawk and its spin characteristics.

The recent controversy relating to this aircraft best illustrates the very essence of why there is an AOPA Air Safety Foundation. Realizing that some AOPA members own the PA-38, and many more have trained or will train in the aircraft, we turned to our sister organization and asked them to thoroughly look at this issue.

The result was not just a report or article, but a comprehensive safety review of the aircraft and its comparison with other trainers. I can assure you the staff time devoted to this effort was significant and covered every side of the equation.

The PA-38 project was led by the Executive Director of the AOPA Air Safety Foundation, Mr. Bruce Landsberg. His attached letter should answer your specific questions and then some.

Feel free to contact either of us if we can provide additional information.

Sincerely,

Phil Boyer

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June 24, 1997 -- Letter from Bruce Landberg, Executive Director, AOPA ASF, responding to Rich Stowell

Dear Rich:

Thank you for your letter to Phil regarding the Air Safety Foundation's Safety Review on the Tomahawk. Since ASF, not AOPA, produced the review, I should provide at least some of the response.

You stated that there are irreconcilable differences between the information in the CFI Checklist article on the Tomahawk and the Piper Report FT-118. The reason for the differences is that in both the CFI Checklist and the ASF Safety Review on the Tomahawk, ASF chose to use the Pilot's Operating Handbook for the PA38 - issued January 20, 1978, and revised April 30, 1981, and not the Piper report FT-118 that you cite. The POH is required on board all aircraft, is studied by each Tomahawk pilot, and is more conservative in every case than FT-118, which, according to Piper, is a flight test report.

Let me respond to each of your statements:

1. In ASF's CFI Checklist, Fall 1996, we said " of its non-traditional design, [the Tomahawk] behaves differently than more conventional...aircraft..."

Stowell: " one would expect to see 'different' behavior in the Beech Skipper as well, the rival to the Tomahawk designed for the same mission profile. The fact that the Skipper has not developed a comparable `reputation' seems to contradict ASF's assertion that the stall/spin characteristics are 'because if its non-traditional design.'"

ASF: Many would agree that the Tomahawk's characteristics in the spin are different from the most common training aircraft, the Cessna 150/152, and those differences are noted in the full ASF safety review. You will see that ASF has numerous references concerning the importance of proper training and checkout in the Tomahawk. The Skipper has some significant aerodynamic differences from the PA38, because it is a different aircraft. Your assertion that because an aircraft looks the same, it should fly the same is probably not what you meant. I suspect Beech had a different philosophy when they built the Skipper.

With regard to the spin entry and recovery being conventional - as you know, each airplane make and model and individual aircraft of that make and model may exhibit slightly different spin characteristics, yet taken as a group, their spin behavior is said to be conventional. Pilots agree that the PA38 spin characteristics are different from other training airplanes such as the Cessna 152. ASF contends that, while this may be true, the PA38 is not so different as to be considered unconventional.

2. You quoted us correctly that " research indicates that the PA38 is involved in roughly twice as many stall/spin accidents...as are the Cessna 150/152 and Beech 77 Skipper..."

Stowell: " taken at face value, then the ASF is implying that it is a wholly acceptable certification standard to have like-missioned airplanes (Tomahawk, 150/152, Skipper) display a range of handling qualities that can lead to a 2:1 margin in stall/spin accident rates. In other words, they're saying that a 2:1 difference is what one would reasonably expect to see given the standard, and therefore it is acceptable."

ASF: There is a philosophical question on how much difference there should be between various aircraft certified under the certification rules that is beyond the scope of this discussion. The certification rules are put in place by the FAA and the industry produces aircraft to meet or exceed the standard. For example, the Piper Aztec and the Aerostar are both certificated under the same rule (identical missions) and have vastly different characteristics. Their accident involvement appears to reflect those differences and pilots understand that. ASF's point is that unless the Tomahawk fails to meet the certification requirements, it is incumbent on pilots and CFIs to understand its nature just as Aerostar pilots need to know their machines.

3. You quoted us as saying, " a one turn spin....the Cessnas should recover within one-quarter to one-half turn following application of spin-recovery inputs; the Tomahawk may require up to 1.5 turns."

Stowell: .5 turns to recover from a one-turn spin??? Is this really what the FAA had in mind when it wrote the spinning requirements in Part 23? Normal category spin requirements are stricter for one-turn spins (must recover within one additional turn) than for one-turn spins in an Acrobatic category airplane (must recover `from any point in a spin' in not more than one and a half additional turns)?"

ASF: As mentioned at the beginning of this letter, we used the PA38 POH as the source for information on for spin recovery. The POH states: " recoveries may take up to 1 . turns when proper technique is used; improper technique can increase the turns to recover and the resulting altitude loss....A one-turn spin, properly executed, will require 1,000 to 1,500 feet to complete." When you quoted Piper as saying that " loss of 1,000 feet was normal for the first turn and recovery," you were quoting from Piper Flight Test-118.

Concerning your question on certification, the Cessna 150/152 series was certificated under Civil Air Regulation (CAR) Part 3, which became FAR Part 23 virtually unchanged. The PA38 was certificated under FAR Part 23 through Amendment 7. The certification requirements allow some latitude as to how an aircraft will comply. In some cases, the aircraft may perform considerably better than the requirement while others meeting the specification do not have as much margin. Both aircraft meet the same spin requirements, but the PA38 is less docile in a spin than the Cessna 150/152 series, a point to be emphasized during a PA38 check-out.

In our assessment, the Tomahawk has a higher involvement in stall/spin accidents because it is different from other light training aircraft by design. This is John Lowery's contention and we agree. Where we disagree is that he alleges the PA38 does not meet the certification requirements. We have not found any information in our research to support his contention, but read on.

4. ASF: " must know that spin recovery procedures are slightly different for the PA-38."

Stowell: " listed procedure is more similar to all the rest than 'slightly different.' I do not know how they arrived at this conclusion. I've collected around 100 published spin recovery procedures for different airplanes and cannot find anything unusual in the listing for the Tomahawk."

ASF: The PA38 POH states: "(a) Apply and maintain full rudder opposite the direction of rotation. (b) As the rudder hits the stop, rapidly move the control wheel full forward and be ready to relax the forward pressure as the stall is broken. (c) As rotation stops, centralize the rudder and smoothly recover from the dive."

The Cessna 152 POH states:. Just after the rudder reached the stop, move the control wheel briskly forward far enough to break the stall."

These are small but significant differences in recovery procedures for training aircraft. Additionally the PA-38 POH describes " immediate effect of applying normal recovery controls may be an appreciable steepening of the nose-down attitude and an increase in the rate of spin rotation." Those characteristics are not described in either the C150/152 or the Skipper's POH. Most pilots agree that a Cessna will recover almost immediately from most spins - the PA38 takes longer. That's important to know.

In the full ASF Safety Review there are excerpts from the POHs of the PA38, Cessna 150/152, Beech Skipper, and the Grumman American Trainer to allow pilots and instructors see the FAA approved procedures of each aircraft.

5. ASF stated that " Tomahawk stall/spin accidents occurred when the pilot may have panicked and began to try alternative control inputs."

Stowell: In 1980, AOPA testified before Congress that spin training should not be reintroduced into pilot training.

ASF: The issue of whether spin training should be a blanket requirement in all primary training goes beyond the scope of this discussion. ASF made it clear in the Safety Review that spin training, prior to solo, from a spin-qualified instructor in the Tomahawk is strongly recommended.

Regarding any suggestion of a conflict of interest with Piper, it was fully disclosed in my Safety Pilot column in February '97 AOPA Pilot that Chuck Suma, president of The New Piper Aircraft, is a member of the Air Safety Foundation's Board of Visitors. There are sixteen other members, including the president of Teledyne Continental (who hasn't fared too well on proposed ADs with AOPA), airline pilots, industry suppliers, and a variety of people and companies who have varied interests and agendas. We do it that way to ensure a good cross section of the aviation community.

Piper has not provided ASF any grants. Our financial base is diversified, so no one organization or group has any financial control. As a non-profit organization, we accept support from many sources and assure those with a commercial interest that they are not buying or renting ASF's objectivity.

ASF DID consult with Piper prior to the publication of the report (as shown in the letter that was provided to Lowery) to verify the technical accuracy of the report. We did the same with the manufacturers of the other 10 aircraft on which we have published safety reviews. Prior to publication, ASF sends a draft of the review to the manufacturer, FAA, NTSB, type clubs, and knowledgeable individuals to check for accuracy.

In the September 6, 1996 letter from Margaret Napolitan, Piper air safety investigator, ASF was asked to make four significant changes to statements in our safety review. We made a modification resulting from only part of one of their requests. We did not make the other three significant changes Piper requested. There were two other minor grammatical changes requested that we did make. If you compare her letter to our Safety Review, you will see exactly where the changes were and were not made.

Lowery was provided with all the information that ASF had. This is hardly the picture of an organization with something to hide. We gain or lose nothing by what happens to the Tomahawk, but we are interested in the truth. We have found in our review of the statistics, and in talking to flight schools that have flown and continue to fly the Tomahawk, that it is a demanding trainer that meets Federal certification requirements. Some schools have flown fleets of Tomahawks for years with no spin-related mishaps.

Incidentally, Rich, you pointed out that:

. You have not read ASF's full Safety Review on the Tomahawk as shown in the references cited on your web site. Enclosed is a complimentary copy of the Safety Review on the PA38. Pilots and instructors may obtain copies of the review through Sporty's Pilot Shop.

. You have no experience in the airplane. At ASF we are fortunate to have a staff member who has several hundred hours in the Tomahawk as a CFI and has conducted many spins with his students. This helped us to understand some of the aircraft's characteristics more fully.

ASF did not publish the safety review to vindicate or validate the Tomahawk. We reviewed its accident history to educate pilots on its flight characteristics. The statistics are accurately reported in the safety review. If, through further investigation, it comes to light that there was a significant error or cover up in the Tomahawk's certification, we'll be right there with you asking for some more answers.

Sincerely,

Bruce Landsberg, Executive Director

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June 10, 1997 -- Letter to Phil Boyer, President, AOPA, from Rich Stowell

Mr. Phil Boyer, President
AOPA
421 Aviation Way
Frederick, Maryland 21701

Dear Phil:

I've been following the Piper Tomahawk stall/spin controversy for some time. In light of recently-received information, and as an AOPA member since 1984, I now have serious concerns not only about the airworthiness of this airplane, but also of allegations of a conflict of interest in the reporting of the "" in CFI Checklist, ": To spin...", published by the AOPA ASF in the Fall 1996.

Enclosed is a copy of information I received from John Lowery, plus brief commentary from me where appropriate. I have published this on the internet (www.west.net/~rstowell/tomahawk.html) so that other pilots can reach a better-informed decision to fly or not to fly in the Tomahawk.

Furthermore, I personally find what appear to be irreconcilable differences between critical information in the AOPA ASF article (AOPA) and Piper Report FT-118 (PIPER). Perhaps you can reconcile the following and put my mind at ease:

AOPA: "because of it's non-traditional design, [the Tomahawk] behaves differently than more conventional ... aircraft...." and later, "it does NOT spin the same way as other common, two-place training aircraft."
PIPER: "Spin entry and recovery is conventional...."

AOPA: "in a one turn spin .... the Cessnas should recover within one-quarter to one-half turn following application of spin-recovery inputs, the Tomahawk may require up to 1.5 turns." --1.5 turns to recover from a one-turn spin???
PIPER: Regardless of the number of turns, "the aircraft will recover in one additional turn after input of anti-spin controls."

AOPA: "the PA-38 may require 1,000 to 1,500 feet" to recover from a one-turn spin.
PIPER: "Altitude loss of 1,000 feet was normal for the first turn and recovery."

AOPA: "spin recovery procedures are slightly different for the PA-38."
PIPER: "The most effective recovery technique was found to be full rudder against spin rotation followed immediately by full forward elevator control...." Nothing "" here. In fact, the Piper POH lists an overall spin recovery procedure that is essentially the same as procedures listed for many, many other light singles (I collect published recovery procedures as a hobby).

AOPA: "some Tomahawk stall/spin accidents occurred when the pilot may have panicked and began to try alternative control inputs." --In 1980, AOPA testified before Congress that spin training should not be reintroduced into pilot training. Now AOPA seems to be blaming pilots for not understanding the "" of Tomahawk spins and for panicking in situations for which specific training was not required/was denied.

Your input to clarify these and other apparent discrepancies will go a long way toward restoring my belief that AOPA continues to work in the best interest of its individual pilot-members.

In the interest of safety,

Rich Stowell
AOPA 863347-3

EPILOGUE: If and when AOPA's response to my letter is received, I will publish it here in full. A few days after mailing my letter, I received copies of correspondence between NTSB, AOPA ASF, and Piper that raises other disconcerting questions regarding potential conflicts of interest. Following are excerpts from those letters that, to my mind, demand an explanation from AOPA:

September 6, 1996 -- letter from Margaret Napolitan (Air Safety Investigation, The New Piper Aircraft, Inc.) to Bruce Landsberg (AOPA Air Safety Foundation), in which she states, "Please find below our comments on and suggested changes to the AOPA Air Safety Foundation's Safety Review regarding the Piper PA-38 Tomahawk...." and in closing, "We deeply appreciate the opportunity to review your report prior to its publication and we hope you will give our comments and suggestions serious consideration."

January 10, 1997 -- letter from Bruce Landsberg (AOPA Air Safety Foundation) to Jim Hall (Chairman, NTSB), in which he states, "There has been considerable discussion and controversy surrounding the Tomahawk. The Air Safety Foundation conducted an independent review with no ties to any of the parties involved....[emphasis added]"

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May 28, 1997 -- Letter to John Lowery from Rich Stowell

Dear John:

Just received the July '97 issue of Aviation Safety with your " Not Closed on PA-38" follow-up article. I'm glad to see that you're not letting 'em off the hook on this serious issue.

To me, the AOPA Air Safety Foundation "" article (CFI Checklist, Fall 1996) opens up a bigger can of worms than it closes. But for the sake of argument, let's assume for a moment the AOPA ASF assertions are true and accurate:

"because of it's non-traditional design, [the Tomahawk] behaves differently than more conventional ... aircraft...." --Then one would expect to see "" behavior in the Beech Skipper as well, the rival to the Tomahawk designed for the same mission profile. The fact that the Skipper has not developed a comparable "" seems to contradict ASF's assertion that the stall/spin characteristics are " of it's non-traditional design".

"ASF research indicates that the PA-38 is involved in roughly twice as many stall/spin accidents ... as are the Cessna 150/152 and Beech 77 Skipper...." --If taken at face value, then the ASF is implying that it is a wholly acceptable certification standard to have like-missioned airplanes (Tomahawk, 150/152, Skipper) display a range of handling qualities that can lead to a 2:1 margin in stall/spin accidents rates. In other words, they're saying that a 2:1 difference is what one would reasonably expect to see given the standard, and therefore it is acceptable!

If that's the case, either the FAA, NTSB, AOPA, or the airplane manufacturers have been derelict in their duty to disclose such information to the end users--pilots and flight schools!

Furthermore, it then follows that FAA pilot training standards make it acceptable to produce pilots who are inherently incapable of handling the range of stall/spin characteristics legally permitted between airplanes designed/certified to satisfy the same mission.

"in a one turn spin .... the Cessnas should recover within one-quarter to one-half turn following application of spin-recovery inputs, the Tomahawk may require up to 1.5 turns." --1.5 turns to recover from a one-turn spin??? Is this really what the FAA had in mind when it wrote the spinning requirements in Part 23? Normal category spin requirements are stricter for one-turn spins (must recover within one additional turn) than for one-turn spins in an Acrobatic category airplane (must recover " any point in a spin" in not more than one and a half additional turns)?

If so, a manufacturer having difficulty certifying a design intended for Normal category operation could simply label it "" or "-spins approved" because it would not recover within one turn (provided, of course, said spin is recoverable within 1.5 turns at any point up through 6 turns)? Sounds like a potential loophole to me.

"Instructors must know that spin recovery procedures are slightly different for the PA-38." --The listed procedure is more similar to all the rest than " different". I do not know how they arrived at this conclusion. I've collected around 100 published spin recovery procedures for different airplanes and cannot find anything unusual in the listing for the Tomahawk.

"some Tomahawk stall/spin accidents occurred when the pilot may have panicked and began to try alternative control inputs." --In 1980, AOPA testified before Congress that spin training should not be reintroduced into pilot training. And now AOPA blames the pilots for panicking in spins that they've perhaps never seen before, and blames them for not understanding the "" of Tomahawk spins to boot. Go figure.

Keep the heat on, John!

Best regards,

Rich Stowell

EPILOGUE: As noted below in John's Attachment A, Piper Aircraft Corp.'s own report on the spin and recovery characteristics of its prototype Tomahawk clearly contradicts many of the AOPA ASF asserions regarding purported "" between Tomahawks and more conventional designs as far as spin and recovery characteristics!

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PRESS RELEASE

14 March 97 -- Lowery Safety Consultants, Inc.

Aviation writer and safety consultant, John Lowery, filed suit on January 13, 1997, in the U.S. District Court, Eastern District of California, (Case No. IV -S-97-015 WBS GGH) against the National Transportation Safety Board and Federal Aviation Administration, for violation of the Freedom of Information Act. Lowery is represented by former FAA Attorney Michael Harrington of Davis, California (916-759-8440).

Following a series of articles concerning fatal accidents in the Piper Tomahawk, Lowery requested several documents containing background data on the PA38-112 from both the FAA and NTSB. In what appeared to be an effort to prevent disclosure, the FAA Atlanta Certification office advised of an eight to twelve month compliance delay and sent a bill for $150.00 per document. Requests for the same or supporting documents to the NTSB were ignored, despite receipts for their delivery.

Following a safety review of the Tomahawk, based on a fatal inadvertent stall spin at Inman, Kansas (CHI94FA097) on March 5, 1994, Lowery wrote FAA Administrator David Hinson urging him to suspend the air worthiness certificate of the PA38-112 before other unsuspecting student pilots and flight instructors were killed. The FAA response was written by the manager, Small Airplane Directorate, which attempted to refute both Lowery's letter and the NTSB accident report. The FAA response, while padded with extraneous facts (that were also refuted by the accident report), essentially attempted to vindicate the testing and certification of the aircraft. The FAA response, however, provided erroneous data on the experimental prototype, claiming that the prototype had a low conventional tail and a 100 HP engine.

The NTSB accident report and photos subsequently obtained from NTSB General Counsel document that the prototype aircraft was in fact modified to a T-tail configuration. The engine was in fact modified to 112 HP. Piper Flight Test Report FT118 (see Attachment A) shows that this T-tail, 112 HP experimental prototype was indeed the aircraft used for the spin certification tests. This particualr aircraft had several aerodynamic enhancements that made it very nice to stall and spin, and FT118 reflects its good spinning characteristics.

Some of the aerodynamic features found on the experimental prototype and later altered by Piper's production team included a reduction in wing ribs from eleven on the prototype to four in the production models. This also included a lightening of the wing spar structure. Wing skin thickness was reduced as well. Combined with the rib and spar changes, this made the wing subject to flexing and oil canning, which causes a variable lift-drag ratio and noticeable variations in stall spin behavior. The wing root glove, vertical fin off-set and engine thrustline angle were changed. These changes, the original designer told NTSB field investigators, made the airplane unpredictable when flying near stall speed and especially during an intentional spin.

No stall spin certification tests for the two conformity (production) aircraft have been provided by FAA or NTSB.

A letter to NTSB chairman Jim Hall (see Attachment B), elicited a response that essentially refuted the NTSB field accident report. For example, where the report (CHI94AF097) showed that the experiemental prototype had been used improperly for spin certification test, Hall stated "The Safety Board could find no evidence to support this." Then he quoted at length the wholly inaccurate letter from FAA's Manager, Certification Branch.

In response to Lowery's lawsuit, the NTSB legal council apologized for the "" response to the FOIA requests. Unfortunately she has attempted to satisfy the suit with innocuous documents and by claiming a " process" and "-client privilege" (work product) on most of the requested information. Furthermore, e-mail, she states, "are not agency records as FOIA uses that term."

"This lawsuit is not about money" says Lowery. "Instead it concerns duties and responsibilities of governament officials and agencies to obey the law. This includes keeping relevant facts in a fatal accident from the public to protect the manufacturer, while the lives of our student pilots and flight instructors remain in great jeopardy."

Lowery has sued the FAA previously for violation of the Freedom of Information Act (IV S 93 1352 EJG GGH). That case was settled following a "" from Federal Judge Edward J. Garcia, United States District Court, Eastern District of California, that the U.S. Attorney resolve the suit informally. Judge Garcia said to the U.S. Attorney, "The plaintiff's response that was received from the FAA was so outrageous I don't blame him for suing you." That case, which was also handled by Attorney Harrington, was settled for $47,000 in attorney's fees.

First hearing on the current lawsuit is scheduled before Federal Judge William B. Shubb on April 7, 1997, in the Sacramento Federal Courthouse Courtroom 2, at 1:30 p.m.

EPILOGUE: The lawsuit has not yet gone to court, as the FAA and NTSB are trying to settle out of court. John has proposed the following: 1. Reimbursement of court and attorney's fees; 2. A letter from the FAA stating that there is "no record of any stall/spin tests having been conducted on the Piper PA38-112 conformity prototypes." Further, John noted that it was intimated to him that Piper is looking to buy a Tomahawk in order to conduct said conformity spin tests for the FAA. Piper will equip the airplane with a spin chute to conduct the spin tests. In other words, it's ok for the rest of us to spin Tomahawks " is" -- sans spin chutes. The factory, however, doesn't trust them enough to do the same -- they want the spin chute mounted, armed, and ready!

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ATTACHMENT A
Excerpted from Piper Aircraft Corp. Development Center, Vero Beach, FLA., Report FT-118, Model PA-38-112, p. 156a:

From the beginning of the design of the PA-38-112, the intention was to certificate the aircraft for aerobatic category spins. With this in mind, a comprehensive spin investigation was begun on the first prototype aircraft, N56346 [NOTE: John Lowery faxed a copy of a picture of this same airplane, N56346, sporting a T-tail], and continued through certification. Except for one flight, all spins were flown with the elevator and rudder set at the maximum travel. One flight during certification was flown with the control surfaces set at the minimum limit. No change in spin characteristics was noted due to the control travel settings.

Spin entry and recovery is conventional [NOTE: This statement from Piper directly contradicts the AOPA ASF's claim that the Tomahawk "does NOT spin the same way as other common, two-place training aircraft."] although some occasional difficulty was noted in inducing a power off spin to the right at extreme aft loadings. Irrespective of the loading or entry or number of turns, the aircraft will recover in one additional turn after input of anti-spin controls [NOTE: This directly contradicts AOPA ASF's claim that the Tomahawk "may require up to 1.5 turns" to recover]. Rotation rate is slower and spin stabilization occurs sooner (1.5 - 2 turns) at aft loadings. Forward loadings result in a lower nose attitude in the spin and stabilization at about three turns. Altitude loss of 1,000 feet was normal for the first turn and recovery [NOTE: Again, this directly contradicts AOPA ASF's assertion that the "PA-38 may require 1,000 to 1,500 feet". According to Piper's own remarks, the prototype Tomahawk behaves a lot more like other spinnable trainers than AOPA ASF leads us to believe.] while a six turn spin and recovery required up to 2,400 feet.

The most effective recovery technique was found to be full rudder against spin rotation followed immediately by full forward elevator control.... [NOTE: This also directly contradicts AOPA ASF's claim that the "spin recovery procedures are slightly different for the PA-38."]

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ATTACHMENT B
21 February 97 -- Letter to Jim Hall, Chairman, NTSB, from John Lowery

References: 1) NTSB CHI 94 FA097; 2) NTSB CHI 95 FA326

Dear Mr. Hall:

Recently the AOPA Air Safety Foundation published information regarding the Piper Tomahawk to advise pilots of the airplane's unique flying characteristics that can lead to an inadvertent stall spin encounter. This information was published in response to an NTSB request by Mr. Paul Alexander (May 22, 1996), a copy of which I received from an individual at the Safety Foundation. This information may be valuable to emphasize the "" (and hazardous) flight characteristics of the Tomahawk. Yet it does the flying public a disservice because of its vindication of the aircraft. In essence it effectively camouflages the serious aerodynamic and structural deficiencies highlighted by NTSB accident report in the Inman, Kansas accident (reference one), and the evidence of stall spin in the carbon copy Danville, Indiana mishap (reference two).

The Inman, Kansas accident report clearly documents significant design and aerodynamic changes made by the production team (e.g. flexible wing); described by the original designer Dr. Richard A. Kroeger and several other former Piper engineers and test pilts (DERs) as making the airplane unpredictable in flight, especially when flying near stall speed and especially during an intentional spin (see statements in reference one).

The AOPA Safety Foundation's Tomahawk review states that the airplane's safety record is slightly worse than similar aircraft: Yet using NTSB data, supplied to me by the Board's Analysis Data Division, the statistics show it to be more than 20 times greater per 100,000 flying hours than comparable aircraft.

The AOPA Safety Foundation's review states that the Tomahawks' [sic] accident history shows the stall spins occurred at very low altitude, "from which recovery could not be expected." The Board implies this erroneously in the Danville, Indiana accident (reference two). Yet this accident report contains an ATC radar plot showing the airplane departed 2500 feet altitude with a 9,000 fpm decent [sic] rate.

For a stalled aircraft such a descent rate at stall certainly does not comply with FAR 23.203 (b)(1) for stall certification. It would be unsafe to practice stalls below 10,000 feet, which is unrealistic for a light training aircraft.

In the Danville, Indiana crash the NTSB's PROBABLE CAUSE was "...inadequate recovery while maneuvering." Further, the NTSB stated "Witnesses reported the airplane flying at an estimated altitude of 500 feet." Yet none of the witness statements in either the NTSB or the Indiana State Police report make this statement. There was however witness evidence of a right hand spin (the non-aviation witnesses called it a spiral) followed by a left hand secondary spin just prior to impact. A police investigator elicited an oral statement from a farmer "working on his combine" that the airplane was at a normal altitude "which could have been 500 feet."

An analyst using this official report is led to believe the pilot was maneuvering at low altitude (500 feet) which is refuted by known evidence. The radar tape, wreckage photographs, and witness statements clearly document an accidental spin from an otherwise reasonable training altitude of 2500 feet.

Because of the Board's curious finding and lack of RECOMMENDATIONS to FAA (to prevent future simialr accidents) the requirement of the INDEPENDENT SAFETY BOARD ACT of 1974 (Section 304 (7) and 307 (a), is thwarted. Thus Piper is saved the expense of an FAA generated Airworthiness Directive that would cost the company thousands of dollars. This statement is based on your previous letter concerning the Board's meeting and recommendations to Piper for "...changes/product improvements that would further enhance the airplanes laterl/directional characteristics at low speed and make it more closely resemble the stall spin resistant PA38-112 experimental prototype." (Your letter dated 05/04/96.) As an Airworthiness Directive this is the correct recommendation. You may recall that this aircraft of course had the stiff 11 rib wing and other significant aerodynamic refinements. It is especially noteworthy that the experiemental prototype rather than the conformity prototype is documented in reference one as the aircraft used to certify the PA38-112 for stalls and spins. (See Piper Flight Test Report 118 and Trevor Smith's sworn testimony). Meanwhile our student pilots and flight instructors continue to be exposed to the very serious hazard of inadvertent and flat spins in this unairworthy aircraft (again, see refences one and two).

The AOPA Safety Foundation's Tomahawk Safety Review was staffed in draft format with THE NEW PIPER AIRCRAFT INC. and major changes made in the final product by Piper Air Safety Investigator Margaret Napolitan (Piper letter dtaed 06/06/96). This document too I received from an individual in the Safety Foundation. It is my understanding Ms. Margaret Napolitan is a former NTSB employee.

It is further noteworthy that The New Piper Aircraft Inc. is listed as one of the sponsoring organizations of the AOPA Safety Foundation. Of additional interest is that the AOPA Safety Foundation has a " of Visitors." The president of The New Piper Aircraft Inc. is one of those members.

Equally worrisome to fair and technically honest accident investigation is the use of a manufacturer's representative on the Danville accident investigation team. While I understand this is traditional, it is noteworthy that the Inman, Kansa accident did not have a Piper investigator. And this team [at Inman] uncovered apparent fraud in the production configuration of the PA38-112. Therefore it appears ethically questionable to allow a Piper investigator to participate as an accident team memebr since the company has an obvious financial interest in the outcome. Then despite the " copy" circumstances of the Danville accident, the Board finds "...pilot lost control while maneuvering."

Based on the overwhelming evidence accumulated in CHI 94 FA097 and CHI 95 FA326 and the very obvious conflict of interest in the AOPA Safety Foundation's recent "" of the PA38-112 aircraft, I urge the Board to issue corrective information to the Foundation's "-approved and sponsored" publication. Further, I once again urge the NTSB to make safety RECOMMENDATIONS regarding the Tomahawk to the FAA, that fulfill the Congressional intent of the Independent Safety Board Act: The evidence in your own accident reports shows clearly that the Piper Tomahawk requires a certification review. And while I regret saying it, there is also ample evidence to justify a criminal investigation into the original certification and production of the aircraft. Human life simply must take precedence over corporate profits. To my mind that is the NTSB's major charter.

Sincerely,

John M. Lowery

 

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