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solent
15th Aug 2017, 15:22
Here is what is in my thought process, well known aircraft, good trainer and time builder, operating costs not too steep.

Purchase price doesn't seem to bad but I know it varies though I really don't have a massive budget (20-30K region), I would like to keep the aircraft either me owning individually or as a small group and eventually move on to upgrading paint/interior/avionics in time.

I looked at the rates of hiring this type from a school, quite high for what it is so after my initial buy in and running costs given I am looking to do a good few hours in it I think I can make it be cost effective.

Anybody else done this or any advice would be welcome.

Genghis the Engineer
15th Aug 2017, 18:09
It's a nice aeroplane to fly, and a good trainer, although I've never owned one.

Biggest piece of advice I'd offer, is get your maintenance company onside before the aeroplane. Have an agreed set of maintenance arrangements, pricing structure, mutual trust, etc - then have one of their people go over any possible aeroplanes before you commit.

G

Zaitcev
15th Aug 2017, 18:38
I looked at PA-38 for a purchase in the U.S. market, and found that Cessna 152 beats it in every performance category while using the same engine. The 152 is a fractionally more expensive on average, but variations in the market are such that it was not a deciding factor for me. This may differ from U.K., of course.

Pilot DAR
15th Aug 2017, 20:55
Though a "Cessna man", I quite enjoyed my PA-38 flying. They're different to fly, but fun, and they do what they say on the box. Be very sure to familiarize yourself with AD's applicable, and how they have been complied, and I recall some kind of airframe time limitations, again, know before you buy. If you read the entire Type Certificate Data Sheet, and any Airworthiness Directives, you should have a good idea of where any given plane is in it's economic life.

If you're going to fly at least 100 hours a year, ownership is a good idea, though passed are the days when you might also sell as an investment afterward.

Hyph
15th Aug 2017, 21:55
I also like the Tommy and found it fun to fly, if a little lively in turbulence. It's not especially quick either, cruising at around 90 knots, so not really a going-places machine.

I believe the wings have a life limit of something like 11,000 hours, the problem being that with most of them used for training, therefore they have high hours so this can be a real issue.

And to address the 152 vs Tommy matter... the 152 might well beat it performance aspects, but in a Tommy you won't feel intimately familiar with person sitting in the right-hand seat - it is significantly more spacious. That may or may not be an advantage, depending on who is occupying said seat.

Forfoxake
15th Aug 2017, 22:45
Have you considered a permit aircraft?

B2N2
16th Aug 2017, 01:10
Probably the worst aircraft that Piper ever built.
There's a lot of info out there including that a Piper design engineer recommended that they should buy them back and shred them.

The certificaton testing the FAA did on the Tomahawk was done with a preproduction model built at the Lock Haven, PA plant. When that plant was destroyed, production was moved to Vero Beach, FL, but not before significant changes were made to the wing.

The new design included the removal of a number of ribs from the wing, reducing it's rigidity, and it was NOT put through new stall and spin testing by the FAA, despite being certified for intentional spins.

After a number of accidents and near misses involving spins, the NTSB reccommended that the FAA reevaluate the aircraft's performance in 1997
http://www.landings.com/_landings/ganflyer/jul25-1997/New-Tomahawk-Tests.html

FWIW, the Tomahawk's stall/spin accident rate is roughly 3 to 7 times higher than that of the 150/152, as discussed in this NTSB letter to the FAA-

http://www.ozaeros.flyer.co.uk/tomahawk/ntsb.htm

Interesting reading, I may fly one, but I sure as heck don't want to stall one, let alone spin one!

Added-
Another interesting read (if you have a spare day)
http://www.geocities.com/cfidarren/r-mccabe.htm
--

http://www.airliners.net/forum/viewtopic.php?t=739709

dera
16th Aug 2017, 05:10
Resale value of a 150/152 is so much higher it makes them a much better buy.

First_Principal
16th Aug 2017, 05:11
Per B2N2's post - if you do ever stall one it makes entertaining viewing if you look back at the tailplane :eek:

I concur with most of the other comments here - nice enough to fly, more room than the 150/152 but they wag their tails, the stalls can be vicious and in my view they could catch out the unwary (as they have on a number of sad occasions).

As I recall the main spar is lifed to around what Hyph said, but this could be extended by 1000hours or thereabouts with a mod.

FP.

B737C525
16th Aug 2017, 05:25
Nice enough to fly, people are saying, but that is only by comparison with its run-of-the-mill American counterparts, in my opinion. If spending my own money, I would be buying something with really good handling, such as an AA-5A or one of the Robins. I thought the Traumahawk was a poor aircraft, and didn't enjoy teaching in it at all. In particular, the spring-trim elevator arrangement really spoiled it. There are much better options, so I'd advise the OP to go back to the drawing board.

I often wonder, how many people wouldn't quit after getting their PPLs, if we taught them in aircraft which handled nicely? I also wonder why Piper and Cessna never bothered sorting their handling out - Piper, in particular, committed some grave misdemeanours (I shudder when i think back to the few years when I occasionally flew a Seneca 1).

Capt Kremmen
16th Aug 2017, 10:46
Lovely quite sedate aircraft. Buy with confidence. Check wing life.

Sillert,V.I.
16th Aug 2017, 12:17
I think the tommie is a great trainer (if you learn in one, you'll have no problem flying most other tricycle singles), but as I did both PPL & IMC in one, I'm unashamedly biased.

Your plan is sound, but finding one that isn't by now well work & tatty might be a challenge. Wing life limits & some parts cost/availability (noselegs?) mean many have been unloved for awhile now.

Once you've got your PPL, a cherokee would likely be a more useful & versatile aircraft; you could buy an early 140 now, but IMO they're too easy to fly to be an ideal trainer.

In an ideal world, I'd say train in someone else's PA38, then go buy a PA28 - the transition is trivially easy.

Forfoxake
16th Aug 2017, 12:31
Having trained in both Cessna 150s and PA-38s (did my first solo in one), I agree with much of what has been said above. However, that was over 25 years ago and I would not dream of buying one now. Unless you really need to fly at night or in cloud,for your budget, you could buy a really nice permit two seater. As long as you are prepared to do some basic maintenance, the running/standing costs would be much lower and it would probably be much more interesting to fly.

SpannerInTheWerks
16th Aug 2017, 14:01
I may fly one, but I sure as heck don't want to stall one, let alone spin one!

I spun one three times: came back white as a sheet (so I was told) after the first;
looked behind me (when I was told I shouldn't) on the second - tail moves around a lot ... and
engine stopped during the third ...

Only aeroplane I've spun and not liked it ...

However, that said, I enjoyed flying and instructing on the PA38 and always thought it was maligned for no really good reason (except spinning).

I think a few pilots have had spinning-related accidents during the course of the past few years, so the comments on this Thread remain as relevant as ever.

simmple
16th Aug 2017, 17:07
Many years ago I instructed with the 38 and found it superior to the 152 as it had more room and could bite so student had respect for what could happen particularly when stalling. Spinning was a pleasure most of the time and predictably, you just needed a few seconds of patience while it recovered.
As a trainer an excellent tool, as for anything else you take your pick.

Collieflyer One
16th Aug 2017, 19:57
PA38 can be purchased for approx 2/3 the price of a C152. The C152 is the better aeroplane. The C152 has no lifed parts other than the engine and the throttle cable. The PA38 has larger fuel tanks as standard although they did produced C152 with the optional long range tanks but they both will suffer from a very poor payload if the tanks are full. The PA38 has many ADs and is not good off a short runway. The biggest thing that determines the value is the engine life left. An engine overhaul will be in the region of £15,000. You might get lucky and operate it well into extension. Remember you will need an 8.33 radio after the 1st January. Both aeroplanes are great fun to fly and the chances are you can sell them again for what you paid. Make sure you get an independent survey done by an engineer prior to purchase. Good luck.

B737C525
16th Aug 2017, 20:33
Thinking back to my post above: if we taught them in aircraft which handled nicely?I wonder how many are posting here with proper experience to offer opinion, beyond private flying in those run-of-the-mill spamcans. I know one poster has experience beyond that (although mostly in sport aircraft, I think, and none of it in transport aircraft) but perhaps the others haven't enjoyed the pleasures of various De Havilland designs (I mean the good ones), expensive Beech products, the flawed but effective Slingsby, etc.

B2N2
16th Aug 2017, 20:55
Thinking back to my post above: I wonder how many are posting here with proper experience to offer opinion, beyond private flying in those run-of-the-mill spamcans. I know one poster has experience beyond that (although mostly in sport aircraft, I think, and none of it in transport aircraft) but perhaps the others haven't enjoyed the pleasures of various De Havilland designs (I mean the good ones), expensive Beech products, the flawed but effective Slingsby, etc.

8000 hrs of instruction in 13 years as full time instructor.
5400 hrs of it SE
Many 100's of spins as I was the designated "spin instructor '.
And now 3.5 years on "transport category" although I fail to see how the last part got bugger all to do with an assessment of the Pa38.
I-fly-for-an-airline-so-I'm-always-right-ofobia?

Cessna engineers should be hung then quartered for putting a cockpit light switch on top of a fuel line ( left side door pillar) and Piper engineers should be shot for putting the fuel selector by your left ankle.
Both should be burned at the stake for their cable and pulley flight controls.

Now...back to the Pa38.....:suspect: I'd urge you to reconsider.

First_Principal
16th Aug 2017, 21:24
Thinking back to my post above: I wonder how many are posting here with proper experience to offer opinion, beyond private flying in those run-of-the-mill spamcans. I know one poster has experience beyond that (although mostly in sport aircraft, I think, and none of it in transport aircraft) but perhaps the others haven't enjoyed the pleasures of various De Havilland designs (I mean the good ones), expensive Beech products, the flawed but effective Slingsby, etc.

To my mind the OP asked a question not only about PA38's but also about the economics of what he was proposing.

Most people have focused on the 'plane and have posted their various opinions, it seems likely that the OP will use this machine in private ops anyway so such info would be valid and quite probably valuable to him or her.

Given my own experience (which is reasonably broad) I don't see any posts I could criticise as being deeply unreasonable about the PA38, nor the 150/152 that has been used as a comparison.

Ultimately, and admittedly not knowing about aircraft pricing in solent's location, I suspect the "expensive Beech products" etc may not be what he or she is interested in?

Also concur with B2N2 (again!) that this is not an enquiry about transport craft so the relevance of that escapes me too?

FP.

A and C
16th Aug 2017, 22:34
Having flown the PA38 for over 500 hours I have a high opinion of it as a training aircraft and consider it far a far better aircraft than the C152 for the task........... however you have to be able to fly to train !

About ten or so years back I got into the aircraft leasing business and the PA38 was my primary option but the wing fatigue life and the then dwindling parts supply made me go for the C152.

I have never looked back from that decision, the Cessna's are still flying long after I would have had to scrap the PA38 and there is a plentiful supply of parts, as far as I can see a PA38 is now only worth the time on the engine and the value of the bits you can part out when the aircraft reaches its spar fatigue life......... sad really because to fly it was a pleasure.

rogcal
17th Aug 2017, 01:35
There is a wing life extension mod available that will extend the wing's life by 7560 hrs.

Did someone say you needed a lot of runway to get a Tommy off the ground?

I used to fly into my friends strip in my Tommy and safely out again.

The strip was 260m long! OK, I would not attempt it if there less than 5 kts of wind straight down the strip and it would be lightly loaded but it could and can be done.

Most of my flying was farm strip flying and believe it or not a Tommy can make and ideal aircraft for that type of flying once you've mastered its idiosyncrasies.

So, to the OP, buy one, love it, fly it. :)

First_Principal
17th Aug 2017, 04:31
There is a wing life extension mod available that will extend the wing's life by 7560 hrs.

That's useful, thanks. In my [incorrect] earlier post I'd recalled it as a lot less than that, (probably based on the various analyses I'd done at one time to determine if it was economic to do to one I was looking at - it wasn't!).

I used to fly into my friends strip in my Tommy and safely out again.

Perhaps worth mentioning to the OP that some did come out with 5" wheels, I'd be a bit more wary of strip conditions with them :ooh:

FP.

Zaitcev
17th Aug 2017, 06:09
Piper engineers should be shot for putting the fuel selector by your left ankle.
I prefer the left side location to Mooney's bottom location. In addition, Piper engineers were smart enough to use a valve with "Off-Left-Right" order, while Mooney is "Left-Off-Right". It's a life and death trick to switch tanks every time. So, you may not like Piper's approach, but it's possible to do worse.

tmmorris
17th Aug 2017, 09:13
To be fair the PA38 has the fuel selector central under the throttle and it requires two hands to select Off - allegedly this was requested by instructors during the aircraft design. I know other Pipers have the fuel selector down and left, and I am one of many who have accidentally selected Off in flight (thankfully I was at 4000 so plenty of time to work out what I'd done...)

hsw_ping
17th Aug 2017, 10:50
Interested in this topic as someone who is looking to buy or join a group at some point, I've been a C152 person mainly with a few hours in a PA38 (I'd personally love a share in a Slingsby Firefly, so if anyone has one going spare......)

Can anyone explain why the low wing-hours for the Piper? I've not been able to get a decent explanation and it seems to be something that people quote a lot, but I'm not sure of the reason.

SWX833
17th Aug 2017, 14:23
I learned to fly on PA38s and ended up owning one for a while. They're a very good aircraft and probably one of the cheapest group A certified aircraft you can get in the UK. I can't comment on the spinning characteristics, but I stalled in them plenty of times without any problems.


The wing spar life of 11,000 hrs can be extended significantly with a mod. In fact the guy who bought mine had this done and it's now up at 12,000 hours and still going strong. I'm not certain, but I think the mod can take it up to 16,000 hours, but it might depend on when it was done (i.e. how near to the 11,000 hrs it was).


There are two versions. The Mk1 has smaller wheels and seems a bit lighter and more sprightly. The Mk2 has larger 6" wheels which are a bit better on grass and loose surfaces, like sand. Worth considering if you intend to go somewhere interesting.


Even a high time example would be a safe enough bet if it's cheap enough. Fly it until it's time is up and recoup your money selling it for spares. Or use it as a greenhouse.

Collieflyer One
17th Aug 2017, 21:30
I would like to point out that I do know what I am talking about and I am in a position to comment. The various run of the mill American spam cans are relatively cheap to buy and operate. I have flown many Vans RV-8s and they have really nice handling and good cruise speeds but at £80,000 for a rough one they can't be considered on cost grounds and they are significantly harder to fly than a PA38. The Bristell NG-5 is a modern 2 seat Rotax powered 2 seater that would be more fun to fly sport aircraft. It would be slightly cheaper to operate since it burns 17 L/hr of mogas as opposed to 23 L/hr Avgas. The LAA permit aircraft will be much cheaper to maintain since you are allowed to do a lot of the work yourself under the supervision of your inspector. The downside is you will need the best part of £100,000 and you still need to build it. Many people go for a Jodel because they are cheap to buy, operate and maintain.

First_Principal
19th Aug 2017, 02:51
Can anyone explain why the low wing-hours for the Piper? I've not been able to get a decent explanation and it seems to be something that people quote a lot, but I'm not sure of the reason.

Surprised no-one has answered before now - spar fatigue is the short answer. You could look up this site (https://www.legislation.gov.au/Details/F2006B05966/37719e75-7f89-47d7-95bb-87789f97be7d) for the AD & further info.

FWIW I learnt a little about aircraft structural fatigue from Nevil Shute's book No Highway, which was an interesting read for a youngster of my time.

At the time of writing this I believe the subject of structural fatigue was fairly speculative but as he was an engineer of some repute I suspect there was a degree of experiential thesis there. Certainly the story pre-dated the Comet issues, but not to a huge degree.

Sorry for the drift, the main thing is to ensure your [prospective] Tommy is up-to-date with all its AD's (there are others) and well in time as this wing spar mod shows..!

FP.

Genghis the Engineer
19th Aug 2017, 07:53
Metal fatigue has been understood pretty well since the investigations into some major railway disasters in the 1880s. What the Comet disasters taught us was about fatigue in pressurised aluminium structures - very much about the initiation mechanisms.

There isn't anything about the Tomahawk's mainspar life that wouldn't have been understood by a good aeronautical engineer in the 1930s - but it is what it is.

G

effortless
19th Aug 2017, 09:02
Anyone ever wonder why we called it the Traumahawk. Wobbly prop is one thing but wobbly empennage?

First_Principal
19th Aug 2017, 10:11
Metal fatigue has been understood pretty well since the investigations into some major railway disasters in the 1880s. What the Comet disasters taught us was about fatigue in pressurised aluminium structures - very much about the initiation mechanisms.

Quite right of course, the Comet issue was specific in that sense. I think the Comet-Shute relationship mix for me was because at the public enquiry the prosecuting(?) lawyer of the time cited No Highway at the outset of the proceedings - probably a bit of theatre to some extent but I guess it impressed me somewhat when I read that.

There isn't anything about the Tomahawk's mainspar life that wouldn't have been understood by a good aeronautical engineer in the 1930s - but it is what it is.

I agree that fatigue per se had been understood for some time but I'm not sure it was especially well understood in terms of aircraft at that time? There are many instances (Northwest 421 in 1948 [publication year of No Highway], and Aloha 243 forty years later, just to name a couple) that would suggest perhaps not.

At least with the PA-38 someone's thought about it beforehand and, looking at the AD, they've done so with a degree of science. Let's hope that works out in practice.

effortless: Anyone ever wonder why we called it the Traumahawk. Wobbly prop is one thing but wobbly empennage?

I shared my initial training between a DH-82 and a PA-38 and can well recall after my first stall/spin session with the PA-38 saying to the instructor 'how many people don't come back after that!'. So maybe its flight characteristics have just traumatised a good number along the way... :}

FP.

Pilot DAR
19th Aug 2017, 11:34
Airframes are intended to flex under load, and the limitations are very clear. When my buddy and I used to dogfight in our 150's, I was amazed to be chasing him around in a 3G turn (yes, I have a G meter), to see the sun light up the top of his wings - the wrinkles in the skin, tip to tip, were profound. Once on the ground again, a quick, nervous check, and everything looked perfectly normal.

Yes, the tail of a Tomahawk wobbles around a bit during a spin (which I did many times), and during flight in turbulence too. As the pilot, ask yourself: Why are you watching backward while you're flying forward? Don't worry about it!

hsw_ping
19th Aug 2017, 17:23
Surprised no-one has answered before now - spar fatigue is the short answer. You could look up this site (https://www.legislation.gov.au/Details/F2006B05966/37719e75-7f89-47d7-95bb-87789f97be7d) for the AD & further info.

FWIW I learnt a little about aircraft structural fatigue from Nevil Shute's book No Highway, which was an interesting read for a youngster of my time.

At the time of writing this I believe the subject of structural fatigue was fairly speculative but as he was an engineer of some repute I suspect there was a degree of experiential thesis there. Certainly the story pre-dated the Comet issues, but not to a huge degree.

Sorry for the drift, the main thing is to ensure your [prospective] Tommy is up-to-date with all its AD's (there are others) and well in time as this wing spar mod shows..!

FP.

Ahhh thank you :) I do just wonder why, given all we know about metal stresses, loads, fatigue etc, that this is still a problem? Hmm.

Airframes are intended to flex under load, and the limitations are very clear. When my buddy and I used to dogfight in our 150's, I was amazed to be chasing him around in a 3G turn (yes, I have a G meter), to see the sun light up the top of his wings - the wrinkles in the skin, tip to tip, were profound. Once on the ground again, a quick, nervous check, and everything looked perfectly normal.

Yes, the tail of a Tomahawk wobbles around a bit during a spin (which I did many times), and during flight in turbulence too. As the pilot, ask yourself: Why are you watching backward while you're flying forward? Don't worry about it!
I can definitely vouch for the flexibility of airframes... Aeros in a rented C152 which regularly made the door pop open mid-flight. Yay(!) Airframe was twisting enough that the latch would just pop right out of the lock... of course could never reproduce on the ground. I believe they had to take one of the maintenance guys up for a couple of loops to show him the problem :) The plane was well-known for it. Also it's slightly lop-sided yoke position. Ahh the little foibles we come to know and love...!

Genghis the Engineer
20th Aug 2017, 14:23
Airframes are intended to flex under load, and the limitations are very clear. When my buddy and I used to dogfight in our 150's, I was amazed to be chasing him around in a 3G turn (yes, I have a G meter), to see the sun light up the top of his wings - the wrinkles in the skin, tip to tip, were profound. Once on the ground again, a quick, nervous check, and everything looked perfectly normal.

Yes, the tail of a Tomahawk wobbles around a bit during a spin (which I did many times), and during flight in turbulence too. As the pilot, ask yourself: Why are you watching backward while you're flying forward? Don't worry about it!

I'd second that - flexibility is a major part of how aircraft structures handle loads - a very rigid structure will suffer much higher transient stresses under variable load than a flexible one.

After all, think what it would do to your spine if the undercarriage and tyres were absolutely rigid, instead of flexible, during landing.

G

Dr Jekyll
20th Aug 2017, 15:07
Surprised no-one has answered before now - spar fatigue is the short answer. You could look up this site (https://www.legislation.gov.au/Details/F2006B05966/37719e75-7f89-47d7-95bb-87789f97be7d) for the AD & further info.




But why does a PA38 have a specified fatigue life while a C152 or PA28 doesn't?

Pilot DAR
20th Aug 2017, 15:54
But why does a PA38 have a specified fatigue life while a C152 or PA28 doesn't?

Probably for the simple reason that objectively, based upon service experience and condition, it was found to be necessary. Cessna wings are so remarkably over built, and simple in structure and inspectability, that fatigue seems never to have been a concern. I used to fly a Cessna 207 with more than 19,000 airframe hours, which was a perfectly fit and fine plane.

PA-28s were the subject of and AD getting on 30 years now, which required wing spar attachment inspection. I understand that the basis for issuance of that AD was statistically skewed. The resulting inspection effort was widely agreed to be doing more damage, than the "no damage" being reported by the first inspections. I believe that the AD was withdrawn.

Different aircraft types have different structural design philosophies, so you simply have to understand that which applies to your aircraft, and manage it accordingly....

Genghis the Engineer
20th Aug 2017, 16:05
So far as I have ever been able to tell, different engineering design philosophies.

Two different approaches are "life by inspection" and "fixed life", both are regularly used on structurally critical components on aircraft. In global terms, the cost of the PA38 mainspar mod is, after all, pretty cheap - it's just a lot of money compared to the second value of a PA38: but not even compared to what a PA38 was new. Think of the happy owners of de Havilland Twin Otters, where the entire wing is lifed and has to be replaced !

G

Dr Jekyll
20th Aug 2017, 17:08
Mildly off topic, but how does the Beechcraft Skipper compare?

tmmorris
20th Aug 2017, 17:56
I'd second that - flexibility is a major part of how aircraft structures handle loads - a very rigid structure will suffer much higher transient stresses under variable load than a flexible one.

If you ever get the chance to be on top of a church tower while the bells are ringing you'll find it flexes. Rather alarming the first time...

First_Principal
21st Aug 2017, 00:20
But why does a PA38 have a specified fatigue life while a C152 or PA28 doesn't?

I recall some controversy over the PA-38 at or after certification in which there was some suggestion that the pre-production aircraft differed from those actually produced. I know there was some issues with stall strips that should be retro-fitted, but what I'm thinking of related to changes in design that could have an effect on fatigue of the main spar.

Without going into a lengthy discussion on fatigue and its various components (there are plenty of learned articles on line) I think the following makes interesting reading:

"Research into the PA-38's design, certification, and manufacture revealed the design originally started out with a conventional tail, i.e., a low mounted horizontal stabilizer/elevator rather than the "T" tail it was certified with. The prototype was designed, built, and test flown during late 1969, 1970 and into 1971. For reasons not defined, the design was placed into storage at the manufacturer for about four years. The PA-38 prototype was taken out of storage and reconfigured with a "T" tail. One of the two original design engineers remained with the company and worked on the resurrected prototype's development.

Originally, the wing was designed using the NASA GAW-1 airfoil and 11 full ribs from wingtip to wing root on each side. This wing had a "U" shaped channel main and secondary spar from wing root to wing tip. The two-piece main spar was joined next to the aileron/flap junction of the wing. Both original design engineers said the PA-38 prototype had been built with a rigid wing structure. One of the design engineers said this type structure is necessary when using the GAW-1 airfoil.

The certificated PA-38 had its main wing spar made from flat aluminum stock. The "U" shaped secondary spar was retained. Lightening holes were cut out along the main spar's outboard half. The main spar had span length "L" shaped extrusions attached to its top and bottom.

The reconfigured airplane retained the same airfoil but had its wing rib numbers reduced to four full sized ribs and four nose ribs per wing. Wing surface shaping extrusions replaced the ribs that were eliminated from the prototype. The extrusions were positioned between the main and secondary spars. There were no vertical braces between the top and bottom extrusions. The original design engineers were asked why the design had been changed. Both said it was their opinion that the airplane's structure had been simplified for manufacturing purposes after it left their design shop. The design engineer said that removing wing ribs and changing the spar design would make the wing less rigid, i.e., "soften" the wing. According to this engineer, the wing's softened structure would not enhance the wing's stall and spin characteristics. He said the softened wing structure could change the airfoil shape, making the wing a new and unknown commodity in stalls and spins. He said he had inspected a PA-38 wing and found it to be very soft, and able to be torsionally twisted without substantial effort.

FAA Service Difficulty Reports related to the wing were examined for the period between 1986 and April, 1995. Fifteen reports showed loose rivets in the wing, bent aft spar attach fitting, and undertorqued wing spar attachment plate bolts. Before sending the airplane to the production design shop, the remaining design engineer stated the airplane had problems with "A very strong rolloff, I think, to the left." He said he designed a wing root glove that was very effective "...in terms of cooling off the stall characteristics." He also revealed the airflow next to the wing root, aft fuselage, and tailcone was not adhering as it should. He said the purpose of the cuff was to improve the airflow along the aft fuselage and give the airplane better stall characteristics. The company production design shop engineers removed the cuffs from the airplane after they had received it from the design shop. The airplane received its FAA type certificate without the leading edge cuffs."

While the above concentrated on flight characteristics [it came about as a result of an accident in 1994] it seems clear to me that there were substantial changes to the structural design that could potentially and negatively affect the wing over time. Moreover there appear to be reported issues that lend support to this view.

In the AD I referenced it was clear that the remaining spar time, post-mod, depended upon pre-mod hours, which are I suppose sufficiently proximate for cycle time (a requirement for cumulative damage/fatigue). Although I've no hard evidence to point to (and don't have time to look further) I don't think it's too long a bow to draw that the fatigue life results from Piper reacting to real issues discovered with the production wing, and that the mod extending spar life dovetails into this and known factors affecting fatigue.

FP.

Big Pistons Forever
21st Aug 2017, 00:24
I have flown the PA 38 including instructing in it. Flying wise it is a pretty decent handling airplane and the killer spin rep is a total myth as there is nothing wrong with the spin characteristics.

The one thing that really put me off the aircraft was the brutally crap build quality. A Yugo looks better built than this aeroplane. It is no coincidence that virtually every flying school has gotten rid of them and in many cases gone back to Cessna 152's.

Personally if you are looking for a good certified 2 seater, go look at the Grumman AA1B or even better a AA1C. Less money than a 152, an honest 10 knots faster and with delightful handing, great visibility, thanks to the canopy, and a surprisingly wide and comfortable cockpit.

I have owned a AA1B for 17 years and found it a cheap and cheerful run about. It has proven very reliable and it is fully supported by Fletch Air.

The Grummans have an excellent type club at aya.org.

Capt Kremmen
21st Aug 2017, 15:01
They surely do restore them or, why the wing spar mod ?


You might have cause to regret a Robin HR100. I owned one and one day the flap deployment motor failed. Getting spares out of Robin is like asking a Yorkshireman for a loan.


The position of the motor in the a/c makes it all but inaccessible. The a/c disappeared for about two months and I received a huge bill. That, plus the bill for the Star annual as it then was removed me from the list of Robin satisfied customers. That said, the a/c was a delight to fly.

Genghis the Engineer
21st Aug 2017, 15:08
I think he wants a Grumman Tiger next.
I have a share in a Cheetah (Tiger with a smaller engine and lower MTOW) and love it for touring, as well as very much preferring it to fly and instruct on to the standard Piper and Cessna products (not that I dislike the PA38 or C152, although I find the PA28 and C172 dull and heavy) - a Tiger would be nicer still.

I've never flown one, but suspect that BPF's views on AA1s may well be good here in the UK also - there's a reasonable amount of expertise around on how to operate and maintain them, and Mattair at Bournemouth are a very ready source of spares if needed for all of the Grummans.

G

irish seaplane
22nd Aug 2017, 10:10
People don't restore Tomahawks in America. Once the engine is done, this are pushed to the weeds.

I had a complete PA38 that was repainted, and de registered in the hope it would go on the N reg. I parted it out rather than spend 4-5k getting it airworthy and going through the hassle of getting a DAR here. It made alot more in parts than I could have got for it flying.

Parson
22nd Aug 2017, 11:16
Learnt to fly in one, including spinning. Nice a/craft and more space than a 152.

If I was looking to buy a 2 seater though, I'd look at something like an RV.

B2N2
22nd Aug 2017, 13:18
I have flown the PA 38 including instructing in it. Flying wise it is a pretty decent handling airplane and the killer spin rep is a total myth as there is nothing wrong with the spin characteristics.


The souls that lost their life in one beg to differ.
Semantics but was it the spin characteristics or how it spun?
The yoke rod would get stuck in the panel in the full aft position thus not allowing for recovery.
Fatalities included flight instructors, examiners as spins are required in the USA for flight instructor training/examining.

Genghis the Engineer
22nd Aug 2017, 18:09
Can you post a link to the accident investigation report on the fatality you're talking about B2N2?

G

B2N2
22nd Aug 2017, 19:57
Can you post a link to the accident investigation report on the fatality you're talking about B2N2?

G

I'll look for it when I'm not on my phone.
In the mean time it's been discussed here before
http://www.pprune.org/archive/index.php/t-309978.html

The issue is mentioned here:

Piper Service Bulletin 661, entitled "Control Column Installation Modification", was issued on August 22, 1979. The purpose for issuance of Piper Service Bulletin 661 was reported as, "It has been reported that roughness or binding of the control shaft in the instrument panel cutout hole can occur when the control wheel is full aft and direct forward or upward-and-forward pressure, rather than linear pressure along the control shaft, is applied. This Service Release contains instructions for the modification of the control wheel shaft bushing assembly to provide a smoother forward movement of the control shaft from a fully aft and up position." A copy of Piper Service Bulletin 661 is attached to this factual report.
Piper Service Bulletin 800, entitled "Elevator Control Travel Modification", was issued on November 19, 1984. The purpose for issuance of Piper Service Bulletin 800 was reported as, "It has been reported that when either control wheel is full aft and an upward-and-forward pressure is applied, the potential exists that the pilot may be unable to move the control yoke out of the full aft position. This Service Bulletin provides instructions to modify the elevator up travel to alleviate the above described problem."
https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20001212X19701&AKey=1&RType=Final&IType=FA

I'll look for more.