Spinnin' the Tomahawk.

[EatSleepFly]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]
but apparently you just wanted to announce to everyone that you're gonna go do a few spins -hip hip hooray.

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[Josh]

Re: Spinnin\' the Tomahawk.

Not really directed at you Ed, but rather the general "i read over at AOPA..." or "I heard from my uncles third brother thrice removed..." and I was showing it is quite easy to find a ton of information on the plane. The few references to problems with spins can certainly be argued with ones that say the problems are a result of not knowing how the airplane reacts.

And, this is the point on my question here. I'm looking for those with experience actually spinning a PA38-112. Not to hoo haa, and say I'm going to do some spins. Not to say if the craft is part of some conspiracy or something. I'm looking for those who have done spins in the aircraft I want to. Especially because there are a lot fewer of these aircraft in service, so finding someone with spin training in them is harder.

Ed, I'm curious what you would consider a "normal" spin recovery? Is it not better to learn actual control inputs that are needed, rather than the if you let go it'll recover method that works well with a hard to spin aircraft? From reading through your posts on the forums here, I am curious as to your training on spins, and what you would do if someone comes to you as a CFI, with an aircraft you don't know, and says, "I wanna do some spins". Lets pick a new plane we know is spin certified. A Diamond Katana. I don't know if you have any time in one, but lets say you don't. Some owner comes to you, as a CFI, and says they want to do some stall and spin practice in their plane, the Katana. With 0 time in it training, or even doing spins, would you do it? Hope that helps give you more of an idea of where I'm coming from in asking the original question here.

 

[derg]

Re: Spinnin\' the Tomahawk.

Are PA 38's even approved for intential spins?

 

[Alchemy]

Re: Spinnin\' the Tomahawk.

Don't know if this has been mentioned, but unless you're training for your CFI rating, you need to be strapping parachutes if you plan to intentionally spin an aircraft. This is due to the fact that your bank angle will exceed 60 degrees and your pitch attitude may exceed 30 degrees. The FARs require all occupants to have parachutes in such situations. The spins also have to be done in an aircraft approved for intentional spins. If you're going to go to all this trouble, why fly a tomahawk? Fly something with decent aerobatic capabilites like a decathlon or a pitts.

As a CFI I wouldn't go up and spin a plane that I had zero time in. I'd definitely want to get a feel for the aircraft with at least a few hours of normal maneuvers first. During my CFI training, I practiced spins on 2 flights, and have done a total of six or seven spins. I recovered from most of those after the first full rotation, but allowed one to develop to three turns. I feel comfortable enough to teach spin entry and recovery techniques with that amount of experience, but a spin is not something I'd want to do intentionally during my first 30 minutes in a new aircraft type.

Would I spin the tomahawk? From what I've just read, probably not.

 

[E_Dawg]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]
Ed, I'm curious what you would consider a "normal" spin recovery?

[/ QUOTE ]
whatever the poh says for that airplane

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Is it not better to learn actual control inputs that are needed, rather than the if you let go it'll recover method that works well with a hard to spin aircraft?

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yes, don't think you'll get disagreement from anybody on that one

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From reading through your posts on the forums here, I am curious as to your training on spins

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took a short and sweet aerobatics course while working on the commercial; haven't logged my # of spins but I'd guess it between 20 - 30.

[ QUOTE ]
what you would do if someone comes to you as a CFI, with an aircraft you don't know, and says, "I wanna do some spins". Lets pick a new plane we know is spin certified. A Diamond Katana. I don't know if you have any time in one, but lets say you don't. Some owner comes to you, as a CFI, and says they want to do some stall and spin practice in their plane, the Katana. With 0 time in it training, or even doing spins, would you do it?

[/ QUOTE ]
I don't think it's a good idea to 'teach' someone spins when you've never even flown the airplane you're trying to teach in. just me though. I do have katana time though, but even then I would get spin training myself in it before teaching someone

[ QUOTE ]
Hope that helps give you more of an idea of where I'm coming from in asking the original question here.

[/ QUOTE ] whatever dude.

Again, even more totally unhelpful info but the production pa38 is different from the experimental prototype. Changes include 11 ribs / wing vs only 4. This information is from 'Anatomy of a Spin'. The guy who wrote it strongly reommends against spinning the airplane and doubts the airworthiness cert of the airplane. Also, had you read that NTSB link (which to me is just a bit more reliable than my uncles mother's aunt) you'd have seen exactly the kind of info you were looking for:

"According to the NTSB, one former test pilot who worked at the Lock Haven facility from 1978 to '84 told the board that the Tomahawks he flew were "totally unpredictable; one never knew in which direction they would roll off, or to what degree, as the result of a stall."

The NTSB also reported that a second former test pilot, who worked for Piper at Lock Haven for six years beginning in 1979, told safety investigators earlier this year that Tomahawks "were very unpredictable in a stall. Each airplane did not perform stalls the same from one flight to the other," the test pilot is quoted as saying.

A third former Piper test pilot, also interviewed by the NTSB earlier this year, reportedly told investigators that production Tomahawks "were nothing like the article certified (by the FAA) as far as stall characteristics are concerned."

I am not saying "don't spin it". Again, I don't care what you do. Just trying to help answer your question.

 

[Josh]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]

I don't think it's a good idea to 'teach' someone spins when you've never even flown the airplane you're trying to teach in. just me though. I do have katana time though, but even then I would get spin training myself in it before teaching someone

[/ QUOTE ]

This is exactly why I'm posting here. I'll likely be instructing in a PA38, so I want the training first.
We don't disagree Ed as I suspect we didn't, and for some weird reason, you seem to think we do from the way I'm reading your posts.

I have read everything that I was able to find on the Tomahawk, which includes all links and reference of real sources that have found their way into this thread, and a few others as well. I do not doubt the aircraft is airworth, or that it can stall and recover, or that it can spin and recover. And that is not what my question is. I'm going by the FAA saying that it can be done according to the certification. And, I've seen others here say they have done it.

The Grumman AA1 series, there is a perfect example. One time certified for spins by the FAA. That certification for intentional spins was removed. Because of that, I would not do intention spins in it. No such thing has been done with the Tomahawk.

I'm keeping this going because so far, I've got 4 comments related to what I asked originally, and may get more. The rest of this is turning into questions of if the plane is airworthy as originally certified, and I'll try and address them as I can, but that seems to be stirring people up a lot for some reason.

Doug, yes.

From the PA38-112 POH Section 4, Normal Procedures, 4.43 Spins
The airplane is approved for intentional spinning when the flaps are fully retracted.

The POH has the following sections, I'll just list the titles, since it all covers 4 pages: before spinning, spin entry, spin recovery, further advice on spinning, mishandled recovery, dive out, engine. Each of these areas are about 100-400 words long. I can type in some text if anyone wants to read it, and doesn't have a POH to look at.

Again, thanks for those that have provided their PA38 experiences, and continue to do so.

There are 2 small schools at my local field that use the Tomahawk as the primary trainer. I use one of them. In my initial training hours for private, during cross controlled stall demos, we got about 1/2 turn around on the recover. Since then I've been interested in doing more with the planes, but that instructor has gone back to an airline job. None of the instructors I am familiar with there currently have done intentional spins in the planes there. I'll be contacting the owner of the other school soon, since it is a short walk away, though they specialize in bringing foreign students in for training.

 

[jdflight]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]
"According to the NTSB, one former test pilot who worked at the Lock Haven facility from 1978 to '84 told the board that the Tomahawks he flew were "totally unpredictable; one never knew in which direction they would roll off, or to what degree, as the result of a stall."

The NTSB also reported that a second former test pilot, who worked for Piper at Lock Haven for six years beginning in 1979, told safety investigators earlier this year that Tomahawks "were very unpredictable in a stall. Each airplane did not perform stalls the same from one flight to the other," the test pilot is quoted as saying.


[/ QUOTE ]


I have stalled Tomahawks at least four days a week for the last 8 months and while I admittedly have not read all the old NTSB reports, I can confidently say that I can predict almost exactly what will happen each and every time. If I couldn't, I would be extremely hesitant teaching the demo stalls and particularly the cross controlled stall. However, even when teaching these, it will roll and pitch the same direction and amount 8 times out of 10. Test pilots or no, that's what I see on a daily basis.

 

[ready2fly]

Re: Spinnin\' the Tomahawk.

Josh, FWIW - our FBO has three Tomahawks and our instructors no longer do spin training in them. Some HAVE done spins in them in the past when students inadvertently spin the aircraft in power-on stalls.

However, spin training is NOT recommmened by any of our CFI's in the T-Hawks for many reasons. One of them is this - which comes from the article Ed posted, which you may have overlooked:

<font color="red">"Since the two-seat trainer was introduced, <font color="black">it has been involved in 51 U.S. stall-spin accidents that resulted in 49 deaths. </font> It also has been the subject of numerous pilot reports regarding its unpredictable stall-spin characteristics and tendency to enter flat spins.

A recent report by the AOPA Air Safety Foundation found that the Tomahawk stall/spin accident rate was nearly double that of comparable training aircraft such as the Cessna 150/152 , Beech Skipper and Grumman AA1." </font>

The reason for the wing flex is due to the fact that Piper - in a cost-cutting move, only built the Tomahawk with 4 wing spars per wing. It's original design - and the one the FAA certified - had 11 spars per wing.

I've flown the Tomahawk many times. Fun little cross-country plane. But, you will not catch me spinning one on purpose.

Best of luck!

R2F

 

[Icaro]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]


The reason for the wing flex is due to the fact that Piper - in a cost-cutting move, only built the Tomahawk with 4 wing spars per wing. It's original design - and the one the FAA certified - had 11 spars per wing.


R2F

[/ QUOTE ]

Is that why the wing has a lifetime fatigue limit of 11,000 hours?

 

[ready2fly]

Re: Spinnin\' the Tomahawk.

No idea. You aparently have the answer to that one, though, so why don't you enlighten us?

While you're at it, please tell us the wing lifetime fatigue limit on the following:

C150
C172
PA28-161

 

[E_Dawg]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]
We don't disagree Ed as I suspect we didn't, and for some weird reason, you seem to think we do from the way I'm reading your posts.

[/ QUOTE ]

I don't disagree with you at all Josh, except I think it's wierd that you would start a thread on 'Spinnin' the Tomahawk' but shrug off some of the information.

Here's one last thing, the guy who wrote it is supposedly a CFI in the pa38:
[ QUOTE ]
The flat spin is entered from an aggravated cross-control stall. Just hold the cross controls thru the first 1.5 turns and the nose will come up. It's about 30 degrees below the horizon, but the controls go 'dead' (i.e. no effect.) recovery is by deploying the flaps momentarily to get the nose to pitch down. Immediately retract the flaps when the nose pitches and then perform a normal spin recovery

[/ QUOTE ]

 

[Josh]

Re: Spinnin\' the Tomahawk.

Yeah Ed. Not trying to shrug it off. I've just already read the stuff posted. Those stories always come up when you say the word Tomahawk it seems, and I wanted to keep away from that here. I do understand it addresses spin behavior in certain configurations in the plane. Which is why, as you agree, you need to go by the POH when doing intentional spins.

The POH states, as you would expect:

Apply full aft control wheel and full rudder in the desired spin direction. This control configuration with the throttle closed should be held throughout the spin. The ailerons must remain neutral throughout the spin and recovery, since aileron application may alter the spin characteristics

So it seems the test situation you quoted is not for a normal intentional spin, as we have agreed should be done per the POH. It may be some part of some testing procedure I am not aware of, and it is good to know, that with a near full after CG, the plane can go to flat spin (something to worry in any plane with a far rearward CG) when cross controls are held. I think this stresses that a prompt proper recovery will be taught and made. Something that may not be done in other training aircraft. And again, the big reason why I want to see how the Tomahawk performs different if it does, before the situation happens with a student.

What do other planes do if cross controls are held, with an aft CG? Cross control will change the spin behavior, but how? I've not seen any test for other aircraft, so wondering.

 

[Icaro]

Re: Spinnin\' the Tomahawk.

R2F, What did I say?

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No idea. You aparently have the answer to that one, though, so why don't you enlighten us?

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I got this figure (11,000hrs) from the AOPA article "Budget Buys: Day Tripper". I was in the market for an airplane, and the Tomahawk was one I was considering. The article just stated the limit as fact, and didn't say why it was so. You're explanation of the reduction in spars to 4 from 11 seemed to be a good explanation as to why the wing had a limit. I thought you may have known, that's it. I read in the article that there is (or soon to be) an STC'd kit available which strengthens the wing and can give you an additional 5,000hrs but that is the maximum.

[ QUOTE ]

While you're at it, please tell us the wing lifetime fatigue limit on the following:

C150
C172
PA28-161

[/ QUOTE ]

None of these have any airframe fatigue limits that I am aware of. I researched all three as a prospective buyer and checked AOPA, Aviation Consumer and type clubs and no one made reference to any limits. Provided they are maintained properly, they'll last a long long time.
The PA-38 is the only GA plane I know of that has some sort of limit on it.

 

[Josh]

Re: Spinnin\' the Tomahawk.

From what I found, the STC moves the number to 18,650 hours on the wing. I'm not sure if any light, single engine, general aviation planes I would want to fly that have 18,000 hours on them. Fabric planes are the most likely to be in this range, and would have been rebuilt and recovered many times by that number of hours.

Found the link at http://www.pipertomahawk.com

 

[PhotoPilot]

Re: Spinnin\' the Tomahawk.

Holy cats! I'm away for a week studying hard and come back to flaring tempers with regards to Tommies?!

I'll back up what JDFlight said. Here in FAT, Tommies are spun often, safely, and with certification according to the TC. They are a different animal than Cessnas and can be predictably spun if a pilot knows what to expect. Most notably, they take a bit of time to stabilize and have an inverted portion of the incipent phase. Recovery in this inverted position can lead to speeds in excess of Vne and has been a major factor in spins which resulted in structural failure of the PA-38s.

It's important to note that Tomahawks had a second flow strip installed on each wing in response to it's 'unpredictable' stall characteristics. This action helped to make the stall buffet more prominent, as some pilots were failing to realize that a full stall had developed. The danger was that uncoordinated control inputs could be made while unknowingly in a stalled condition leading to inadvertant spins. I have done most of my primary training in Tomahawks and can attest to their predictable nature when familiarized with the plane's characteristics. I've also flown 172s, PA-28s, PA-44s, and SR22s in my short flying life and find that they all have their quirks. It just seems that the PA-38s had a bad start and people haven't given them a chance since then.

They're great fun to fly, offer wonderful, safe challenges, and provide an excellent training platform, IMHO. They haven't been made for a while and there aren't that many out there . . . so if you don't like them, cool! That means there are more for me!

 

[agcatman]

Re: Spinnin\' the Tomahawk.

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I'll back up what JDFlight said. Here in FAT, Tommies are spun often, safely, and with certification according to the TC. They are a different animal than Cessnas and can be predictably spun if a pilot knows what to expect. Most notably, they take a bit of time to stabilize and have an inverted portion of the incipent phase. Recovery in this inverted position can lead to speeds in excess of Vne and has been a major factor in spins which resulted in structural failure of the PA-38s.

*good stuff snipped*

[/ QUOTE ]

Excellent post.

 

[ready2fly]

Re: Spinnin\' the Tomahawk.

[ QUOTE ]
I got this figure (11,000hrs) from the AOPA article "Budget Buys: Day Tripper". I was in the market for an airplane, and the Tomahawk was one I was considering. The article just stated the limit as fact, and didn't say why it was so. You're explanation of the reduction in spars to 4 from 11 seemed to be a good explanation as to why the wing had a limit. I thought you may have known, that's it.

[/ QUOTE ]
Icaro - hey - thanks. I definitely ready your post the wrong way! My apologies.

I called my FBO and asked about the wing life limits and you're right - 11,000 on the T-bird and none on any of the others I mentioned.

We've had one Tomahawk that reached that limit and was promptly dismantled and sold for scrap. The remaining three we have are still about 3,000 hours from their fate as beer cans.

 

[PhotoPilot]

Re: Spinnin\' the Tomahawk.

Just a few more thoughts after my post from last night.

First, the tommy has only one wing spar. The original 11 wing ribs were reduced to 4 ribs with two stiffeners after it was shown that the original 11 rib wing was significantly overbuilt. The change was made with FAA and engineering approval. In fact, there has never been a structural failure of the wing in a PA-38 that wasn't accompanied by an airspeed that was well past Vne. Along the same lines, the empennage has never had any documented failures despite the rumors of separation during spins.

Also, the same report that mentions "an unusually high Tomahawk stall/spin accident rate, nearly double that of comparable training aircraft such as the Cessna 150/152, Beech Skipper and Grumman AA1" also says, "many of these stall/spin accidents occurred at low altitude, in some cases so close to the ground that recovery would have been impossible regardless of aircraft type."

Further, "The "aggressive" spin reputation of the Piper PA-38 Tomahawk has more to do with pilots than the airplane, according to the latest type-specific safety review produced by the AOPA Air Safety Foundation."

"The Air Safety Foundation warns that even extra altitude and correct pilot reaction may not be enough if a pilot unfamiliar with Tomahawk spin characteristics panics.

"Nose down, opposite rudder and neutral ailerons may first speed up a Tomahawk spin, causing inexperienced pilots to panic," observed Landsberg. "Experimenting with the wrong control inputs will delay or stop recovery."

"Despite that, the report refutes the widely held belief that the type is dangerous overall. The Tomahawk total accident rate is only slightly higher than comparison aircraft, with 7.4 accidents per 100,000 flight hours compared to 6.8 for similar aircraft."

Pilots used to spinning other, more mellow training aircraft would udoubtedly be surprised by the spin attributes of the Tomahawk. Patience and training are needed to understand the behavior of the PA-38 through a spin. Knowing how to spin another plane isn't necessarily enough. For comparison, however, a Pitts, Extra, or other dedicated aerobatic plane makes the Tomahawk look mellow in comparison. It is NOT unreasonable in behavior.

Please don't be affraid of the PA-38. It's a great little airplane. At the same time, give it the same respect that any new airplane deserves. Get checked out in it and, if you plan on doing spins, get airplane specific training.

 

[Eight_Two_Victor]

Re: Spinnin\' the Tomahawk.

Just backing up JDFlight and Photopilot:

I have over 700 hours in Tommies and have never experienced any unpredictable stall characteristics. I've spun a Tomahawk about 15 times and have never had any trouble recovering. In fact, the T-tail design makes the rudder very effective in stopping the spin.

On another note, I feel fortunate to have had so much experience in Tomahawks. They are a lot of fun to fly. Also the visibility in a Tomahawk is the best I've ever seen from any airplane.