Why does the PA-38 Tomahawk have a wing life of 11,000 hours?
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So how many types would you use in a PPL course? I've generally felt that allowing a student to get to know one type throughout was best.
Base type (e.g. PA28) and the PA38 for spins and stalls.You don't need to get to know the PA38 type in order to get the most out of doing a few hours stalls (and spins if you want to), all you need are basic flying skills and a half-decent instructor.
Rest of the time can be spent getting familiar with and enjoying the base type.
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The price difference between the two puts the PA28 into a different group.
Also as well the PA28 isn't really suited to be teaching people to land in. Yes you can do it but as an instructor you have to be very protective of the landing gear. PA38 with its sprung gear you can afford to let them screw it up quite spectacularly and the only thing hurt is the students pride.
The there is the thing with only having one door. Personally I like the idea of being able to get out both sides. Fuel selector unless you have a thing for sticking your face into students crotches on trial flights is much better on the PA38.
These days you can do your PPL in a PA38 for about 5500-6000 if you do it in a PA28 your 7000-8000. I wouldn't say that you get any real benefit from a training point of from flying a touring aircraft. Just gives you a false sense of stability as everything is designed damped to death.
Also as well the PA28 isn't really suited to be teaching people to land in. Yes you can do it but as an instructor you have to be very protective of the landing gear. PA38 with its sprung gear you can afford to let them screw it up quite spectacularly and the only thing hurt is the students pride.
The there is the thing with only having one door. Personally I like the idea of being able to get out both sides. Fuel selector unless you have a thing for sticking your face into students crotches on trial flights is much better on the PA38.
These days you can do your PPL in a PA38 for about 5500-6000 if you do it in a PA28 your 7000-8000. I wouldn't say that you get any real benefit from a training point of from flying a touring aircraft. Just gives you a false sense of stability as everything is designed damped to death.
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PA38 Economics
Ten years ago I would have wholeheartedly agreed with Mad Jock but things have moved on and my agreement with the Scotsman in the subject has fallen to 60%, the fuel burn of the PA38 is it's big advantage with it being £26/ hour cheaper to operate than a PA28.
Maintenance is the rapidly growing problem for the PA38, parts are becoming harder to source and due to the airframe life issues PMA suppliers are not willing to invest in parts production for a type that they see only having a limited life. The aircraft also has some limited life items in the back end with fin support frame and fin spars being the usual suspects for replacement, this work is quite labour intensive and so expensive. You can offset some of this cost by buying cheap aircraft from those who are withdrawing the aircraft from service but the chances are these aircraft will have the same worn items as the aircraft you own.
The best game in town for training from the economic point of view is the Cessna 152, the aircraft is a very "sorted" Cessna 150 having evolved from a good aircraft it has all the major problems of the 150 addressed and the same fuel burn per hour as the PA38.
The Cessna Supplemental Inspection Directive checks (SID's) is a major cost issue and only the penny pinching low hours group owned aircraft owners will ignore these checks as doing so will save them money in the short term while turning the aircraft into a worthless asset. Those who operate the C152 on a commercial basis would be wise to take heed of the SID's program as if it is fully implemented it will guarantee another 10-15000 hours working life from the airframe, something that the PA38 can't offer even if you do the spar life extension modification.
Right now I can hear the Rotax engined light sport brigade muttering things about over weight Lycosorus powered antiques that should be pensioned off, the problem with the new breed of light sport aircraft is they lack the robustness required of a training aircraft, I am seeing the same issues in terms of landing gear & exhaust cracks, pulled rivets and general wear and tear on 150-200 hour Sportcruisers that I see on 15,000 hour Cessna 152 aircraft. The fact is that these aircraft are built down to a weight and what gives is the robustness required to endure the training environment. From what I have seen most light sport aircraft are unlikely to see the other side of 2000 hours and that is why Piper & Cessna have dropped the idea of being involved in this end of the market.
So the conclusion of all of this is that the PA38 regrettably has not the airframe life to warrant much in terms of investment, the light sport aircraft are too fragile to re-pay the capital investment over their relatively short life expectancy so for the task of training the Cessna 152 is the only game in town that makes any sort of financial sense.
Maintenance is the rapidly growing problem for the PA38, parts are becoming harder to source and due to the airframe life issues PMA suppliers are not willing to invest in parts production for a type that they see only having a limited life. The aircraft also has some limited life items in the back end with fin support frame and fin spars being the usual suspects for replacement, this work is quite labour intensive and so expensive. You can offset some of this cost by buying cheap aircraft from those who are withdrawing the aircraft from service but the chances are these aircraft will have the same worn items as the aircraft you own.
The best game in town for training from the economic point of view is the Cessna 152, the aircraft is a very "sorted" Cessna 150 having evolved from a good aircraft it has all the major problems of the 150 addressed and the same fuel burn per hour as the PA38.
The Cessna Supplemental Inspection Directive checks (SID's) is a major cost issue and only the penny pinching low hours group owned aircraft owners will ignore these checks as doing so will save them money in the short term while turning the aircraft into a worthless asset. Those who operate the C152 on a commercial basis would be wise to take heed of the SID's program as if it is fully implemented it will guarantee another 10-15000 hours working life from the airframe, something that the PA38 can't offer even if you do the spar life extension modification.
Right now I can hear the Rotax engined light sport brigade muttering things about over weight Lycosorus powered antiques that should be pensioned off, the problem with the new breed of light sport aircraft is they lack the robustness required of a training aircraft, I am seeing the same issues in terms of landing gear & exhaust cracks, pulled rivets and general wear and tear on 150-200 hour Sportcruisers that I see on 15,000 hour Cessna 152 aircraft. The fact is that these aircraft are built down to a weight and what gives is the robustness required to endure the training environment. From what I have seen most light sport aircraft are unlikely to see the other side of 2000 hours and that is why Piper & Cessna have dropped the idea of being involved in this end of the market.
So the conclusion of all of this is that the PA38 regrettably has not the airframe life to warrant much in terms of investment, the light sport aircraft are too fragile to re-pay the capital investment over their relatively short life expectancy so for the task of training the Cessna 152 is the only game in town that makes any sort of financial sense.
On the subject of SIDs, the CAA ratified their own interpretation of the Cessna 100/200 series SIDS at the beginning of September.
The new SID checks are now no longer mandatory although one may need to make a formal declaration as to why one has chosen not to carry them out. However the cost of owning a 152 as a trainer just went down considerably, i.e. no potential SIDs to break the bank shortly.
IN-2013/138: The Cessna Aircraft Company Supplemental Inspection Documents (SIDs) ? 100/200 Series Aircraft | Publications | About the CAA
"Cessna have published SIDs for its 100/200 series aircraft.
They are not included in the airworthiness limitations sections
of the Cessna Instructions for Continuing Airworthiness (ICA),
and are not subject to any Airworthiness Directives.
Therefore, Cessna SIDs for 100/200 series are not mandatory
inspections from a regulatory point of view, even though they
may be designated "mandatory" by Cessna."
"The Owner/Operator must consider the relevance of any new or
revised ICA, taking into account the type of operation being
undertaken, the aircraft utilisation, age and general condition.
Before making a decision not to incorporate the new material
into the Maintenance Programme, careful consideration should be
given to the potential airworthiness and safety consequences of
this course of action. If it is decided not to adopt the new
ICA, an entry should be made in the aircraft’s maintenance records
that the ICAs apply to their aircraft, but have not been adopted.
If it is decided to carry out the inspections, then the
Maintenance Programme must be amended to include the relevant tasks"
The new SID checks are now no longer mandatory although one may need to make a formal declaration as to why one has chosen not to carry them out. However the cost of owning a 152 as a trainer just went down considerably, i.e. no potential SIDs to break the bank shortly.
IN-2013/138: The Cessna Aircraft Company Supplemental Inspection Documents (SIDs) ? 100/200 Series Aircraft | Publications | About the CAA
"Cessna have published SIDs for its 100/200 series aircraft.
They are not included in the airworthiness limitations sections
of the Cessna Instructions for Continuing Airworthiness (ICA),
and are not subject to any Airworthiness Directives.
Therefore, Cessna SIDs for 100/200 series are not mandatory
inspections from a regulatory point of view, even though they
may be designated "mandatory" by Cessna."
"The Owner/Operator must consider the relevance of any new or
revised ICA, taking into account the type of operation being
undertaken, the aircraft utilisation, age and general condition.
Before making a decision not to incorporate the new material
into the Maintenance Programme, careful consideration should be
given to the potential airworthiness and safety consequences of
this course of action. If it is decided not to adopt the new
ICA, an entry should be made in the aircraft’s maintenance records
that the ICAs apply to their aircraft, but have not been adopted.
If it is decided to carry out the inspections, then the
Maintenance Programme must be amended to include the relevant tasks"
Right now I can hear the Rotax engined light sport brigade muttering things about over weight Lycosorus powered antiques that should be pensioned off, the problem with the new breed of light sport aircraft is they lack the robustness required of a training aircraft, I am seeing the same issues in terms of landing gear & exhaust cracks, pulled rivets and general wear and tear on 150-200 hour Sportcruisers that I see on 15,000 hour Cessna 152 aircraft. The fact is that these aircraft are built down to a weight and what gives is the robustness required to endure the training environment. From what I have seen most light sport aircraft are unlikely to see the other side of 2000 hours and that is why Piper & Cessna have dropped the idea of being involved in this end of the market.
But, the microlight schools have shown massive and successful use from the C42 and various Thrusters, as well as in much smaller numbers the Medway SLA, numerous similarly constructed flexwings, and older types such as the AX3/2000. There are aircraft in that category which will provide that sort of robustness - of which the C42 seems to be current best of the bunch. There are plenty in flying schools flying 400++ hours per year with fantastic reliability.
Of course the C42 mysteriously has about the same sex appeal as a C152 - it's just a similarly excellent training aeroplane which unglamorously does exactly what it say on the tin (albeit at about half the running cost of a C152).
Back to the PA38 - yes, it's proven to be a poorly engineered aeroplane for long life, but that doesn't in my opinion detract from it being an excellent training aeroplane for any given flight or course - for all the reasons Jock explains so well.
G
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Fostex
You are 100% correct from the regulatory point of view and the unwise are delighted that the SID's are not mandatory.
Having done the SID's on one airframe and almost finished a second one ( both in the 10-13000 hour range) I can tell you that the SID's program is a well reasoned and necessary program for aircraft of this age and flight hours. If you have an aircraft that lives in a heated hangar and has flown only 1500 hours the it is a bit over the top but few aircraft meet this description.
If you are a wise owner of a 152 you will have a good look at the program and start doing the bits of the SID's that you think are the most likely to be needed, then the bits that can be done on a low cost opportunity basis while other inspections are being done but you ignore the program at your peril because things will come along to bite you in the wallet............. Or far far worse !
There was nothing on my aircraft that would have resulted in any airworthiness issues in the next 1000- 1500 hours but the early detection of light corrosion and the treatment of these areas will have undoubtedly saved me a lot of money in the medium term when combined with the recommended corrosion control program. Reliability is also an issue that the commercial operator need to consider the aircraft that has had the SID's program done has had no unscheduled maintenance done over the past eight months of club flying, maybe this sort of reliability is not required for a flying group but for some of us it is.
Quite frankly I think that it is foolish to ignore the SID's but from a commercial point of view I am quite pleased that some take this view as these aircraft will provide a rich haul of cheap spare parts for those of us who have taken the trouble to keep the airframes in good order.
Having done the SID's on one airframe and almost finished a second one ( both in the 10-13000 hour range) I can tell you that the SID's program is a well reasoned and necessary program for aircraft of this age and flight hours. If you have an aircraft that lives in a heated hangar and has flown only 1500 hours the it is a bit over the top but few aircraft meet this description.
If you are a wise owner of a 152 you will have a good look at the program and start doing the bits of the SID's that you think are the most likely to be needed, then the bits that can be done on a low cost opportunity basis while other inspections are being done but you ignore the program at your peril because things will come along to bite you in the wallet............. Or far far worse !
There was nothing on my aircraft that would have resulted in any airworthiness issues in the next 1000- 1500 hours but the early detection of light corrosion and the treatment of these areas will have undoubtedly saved me a lot of money in the medium term when combined with the recommended corrosion control program. Reliability is also an issue that the commercial operator need to consider the aircraft that has had the SID's program done has had no unscheduled maintenance done over the past eight months of club flying, maybe this sort of reliability is not required for a flying group but for some of us it is.
Quite frankly I think that it is foolish to ignore the SID's but from a commercial point of view I am quite pleased that some take this view as these aircraft will provide a rich haul of cheap spare parts for those of us who have taken the trouble to keep the airframes in good order.
Last edited by A and C; 3rd Dec 2013 at 16:05.
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Jock
In an ideal world I would totally agree with you but in a practical world the state of play with PA38 maintenance and parts supply is approaching the time when it will be imposable for training providers to achive a reliable service using the PA38.
No one regrets this more than me but it is the way it is.
No one regrets this more than me but it is the way it is.
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I wouldn't say that you get any real benefit from a training point of from flying a touring aircraft. Just gives you a false sense of stability as everything is designed damped to death.
Also as well the PA28 isn't really suited to be teaching people to land in.
It is also more manageable for gusty crosswind landings than a PA38 which would be all over the place.
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I am an ex front row rugby player when teaching in a C150/152 I have one arm over the back of the seats and my hips twisted through an angle. Just so I am not sitting on the students and they have a clear space to fly the aircraft. Door shutting is a game of doors, one side closes the other side pops open. The seat is always max travel back.
Tommy I can sit straight and my shoulders don't touch the student or the side of the aircraft and I don't have the seat at max travel. I will grant you the PA28 is similar but I comparison to the other two seater's it is roomy.
Tommy I can sit straight and my shoulders don't touch the student or the side of the aircraft and I don't have the seat at max travel. I will grant you the PA28 is similar but I comparison to the other two seater's it is roomy.
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I it would seem have a stature much the same as Mad Jock and find that my experience with the PA38 is much the same in terms of comfort.
The cross wind thing and landing thing mentioned by Mixture I simply don't understand unless an approach speed of greater than 1.3Vs is being used.
About twenty years back when I was instructing almost full time we had a bunch of budding airline pilots as instructors who had swallowed the whole airline thing hook, line & sinker. The result of this was hugh circuits so as to accommodate the very long so called stabilized approaches with airspeed increments added to the Vref ( as they called it ). All this resulted in landings that aimed for just inside the numbers at the threshold and actually happened nearer to the other end of the runway.
As most instructing is done at below MTOW just flying the flight manual 1.3Vs as an approach speed is enough as the real Vs for the weight is lower than that quoted in the flight manual and that provides you with a little airspeed margin. If you are at MTOW and you have a very gusty day you might want to add 5 KTS but no more as all that will result is the floating just above the runway described in a number of posts above and the inconsistent landings that hamper student progress.
Roll on twenty years from working with the big circuit and long "stabilized approach" brigade and I find myself flying a B737-800 into Chambray, no long straight stabilised approach but a speed stable approach with a constant rate of turn and decent onto a short runway, this from a visual circuit that would fit inside some of the efforts from my former employers instructors. The one thing all of these landings have in common is that they are flown at the correct speed.
Fortunately I now find myself instructing PPL students at a Military flying club were we can as the student progresses introduce the standard military curcuit with a curving final approach, the students thrive on this achiving very good control coordination and speed control with the time to solo usually 10-12 hours.
The instructing staff are all from professional aviation and all long in the tooth with nothing to prove and who ensure the aircraft is flown in accordance with the flight manual Not in accordance with any of the Folklore that seems to inhabit some flying clubs.
The cross wind thing and landing thing mentioned by Mixture I simply don't understand unless an approach speed of greater than 1.3Vs is being used.
About twenty years back when I was instructing almost full time we had a bunch of budding airline pilots as instructors who had swallowed the whole airline thing hook, line & sinker. The result of this was hugh circuits so as to accommodate the very long so called stabilized approaches with airspeed increments added to the Vref ( as they called it ). All this resulted in landings that aimed for just inside the numbers at the threshold and actually happened nearer to the other end of the runway.
As most instructing is done at below MTOW just flying the flight manual 1.3Vs as an approach speed is enough as the real Vs for the weight is lower than that quoted in the flight manual and that provides you with a little airspeed margin. If you are at MTOW and you have a very gusty day you might want to add 5 KTS but no more as all that will result is the floating just above the runway described in a number of posts above and the inconsistent landings that hamper student progress.
Roll on twenty years from working with the big circuit and long "stabilized approach" brigade and I find myself flying a B737-800 into Chambray, no long straight stabilised approach but a speed stable approach with a constant rate of turn and decent onto a short runway, this from a visual circuit that would fit inside some of the efforts from my former employers instructors. The one thing all of these landings have in common is that they are flown at the correct speed.
Fortunately I now find myself instructing PPL students at a Military flying club were we can as the student progresses introduce the standard military curcuit with a curving final approach, the students thrive on this achiving very good control coordination and speed control with the time to solo usually 10-12 hours.
The instructing staff are all from professional aviation and all long in the tooth with nothing to prove and who ensure the aircraft is flown in accordance with the flight manual Not in accordance with any of the Folklore that seems to inhabit some flying clubs.
A & C, excellent post!
The only suggestion is to remark that 1.3 Vs is Vat ie speed At Threshold - as you say maybe an extra 5 on a windy day.
On certain single engine aircraft I have even calculated 1.3 Vs for different weights (allowing for airspeed position error at both stall speed and 1.3Vs) which is revealing and interesting!
Am also with you all the way about those bomber circuits and like you have also done tighter circuits on circle to land in B738.
The only suggestion is to remark that 1.3 Vs is Vat ie speed At Threshold - as you say maybe an extra 5 on a windy day.
On certain single engine aircraft I have even calculated 1.3 Vs for different weights (allowing for airspeed position error at both stall speed and 1.3Vs) which is revealing and interesting!
Am also with you all the way about those bomber circuits and like you have also done tighter circuits on circle to land in B738.
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Actually, it is actually quite useful in that if you don't get it right, it'll happily float half way down the runway.
It is also more manageable for gusty crosswind landings than a PA38 which would be all over the place.
It is also more manageable for gusty crosswind landings than a PA38 which would be all over the place.
And PA38 isn't all over the place if you have full flap and the right speed. And as we are talking about a trainer then fact that the student can control a more difficult aircraft than the more sedate touring aircraft means that they are pretty much set up for life. And the two seater tommy has done its job as a trainer.
Now we just need someone to produce a modern equivalent of the tommy. Nothing that's come out gets anywhere near the usefulness of the tommy for teaching people to fly.
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Now we just need someone to produce a modern equivalent of the tommy. Nothing that's come out gets anywhere near the usefulness of the tommy for teaching people to fly.
They're affordable new, and they claim that they've solved the nose leg problems, so you should still be able to teach someone how to land it. Nothing will ever be as robust as a Tommy, but they've had their day and it's time to let go.
They have a rotax engine, so won't need to carry as much fuel, so the 600KG MTOM shouldn't be a problem, might actually be able to do a mass and balance and have it work, unlike a PA38 or C152.
All in all a very comfortable aircraft, with great vis, I just wonder how that massive screen will hold up to flying school use and abuse.
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but they've had their day and it's time to let go.
But its only a tool to do a job, the major part of the quality of pilot produced will still be sitting in the RHS.
Speaking of trainers, albeit of the multi engine variety, Perimeter airlines in Winnipeg recently decided to close their flight school. They ran 3 Beechcraft Travel Air twins. The low time one has 19,000 + hrs but incredibly the highest time airframe is just short of 40,000 hrs 
There is no way spam cans like the Seneca/Seminole/Duchess would ever make it to those times. Ditto for the Tupperware specials like the DA 42 and the high wing Rocrap powered toy whose name escapes me. They don't build them like they used to !
There is no way spam cans like the Seneca/Seminole/Duchess would ever make it to those times. Ditto for the Tupperware specials like the DA 42 and the high wing Rocrap powered toy whose name escapes me. They don't build them like they used to !
In fairness, longevity of an airframe all depends on the maintenance organisation.
Despite all passing certification there can often be marked differences in the quality of the work.
Despite all passing certification there can often be marked differences in the quality of the work.