Crazy arse idea - swap engines . . .

[comanchepilot]

As many of you know - I own a 260C Piper Comanche.

Lets assume that I love the way my airplane is set up avionics wise. Sooner or later I will need an new/rebuilt motor.

Lets say there is identical year Turbo 260C Comanche available for sale. With 350 hours on the motor and turbos and new prop.

All of the accessories are the same.

Lets say I can buy this Turbo model, remove the firewall forward and simply drop in the 'new' mount, engine, prop and accessories. Yet - it is essentially a bolt on process. The only thing I keep from my existing airplane is that is engine mounted is the back up vacuum system - I must also remove the throttle, mixture, and rpm cables and housing itself, since the new engine has a manual waste gate.

An 'new specs' engine rebuild with a new prop in my airplane is about $45k assuming my crank is ok.

Lets assume I can buy this airplane for $75k. Lets assume the bolt on process is $10000 - since it on and on for 2 airplanes - total cost $85k.

then lets assume that a 1971 Comanche 260C with steam gauges and a run out engine can command somewhere around $60k in the marketplace.

Assuming that I now have a Turbo'd 260C with the killer avionics in my airframe - and since I have not removed anything from my airframe the 337's are still valid for the avionics - have I truly saved $20k? And gotten alot more utility out of my airframe with the turbo?

Is the FAA going to care any further of my assuming I get proper signoffs?

\Would this process affect the value of the airplane with my 'old' engine on it - assuming you get all the logs and the signoffs? It's still a Comanche 260C with the normally aspirated engine - the Type Certificate is the same I think -

Thoughts?

 

[wabower]

What's the price risk on the sell side?

As many of you know - I own a 260C Piper Comanche.

Lets assume that I love the way my airplane is set up avionics wise. Sooner or later I will need an new/rebuilt motor.

Lets say there is identical year Turbo 260C Comanche available for sale. With 350 hours on the motor and turbos and new prop.

All of the accessories are the same.

Lets say I can buy this Turbo model, remove the firewall forward and simply drop in the 'new' mount, engine, prop and accessories. Yet - it is essentially a bolt on process. The only thing I keep from my existing airplane is that is engine mounted is the back up vacuum system - I must also remove the throttle, mixture, and rpm cables and housing itself, since the new engine has a manual waste gate.

An 'new specs' engine rebuild with a new prop in my airplane is about $45k assuming my crank is ok.

Lets assume I can buy this airplane for $75k. Lets assume the bolt on process is $10000 - since it on and on for 2 airplanes - total cost $85k.

then lets assume that a 1971 Comanche 260C with steam gauges and a run out engine can command somewhere around $60k in the marketplace.

Assuming that I now have a Turbo'd 260C with the killer avionics in my airframe - and since I have not removed anything from my airframe the 337's are still valid for the avionics - have I truly saved $20k? And gotten alot more utility out of my airframe with the turbo?

Is the FAA going to care any further of my assuming I get proper signoffs?

\Would this process affect the value of the airplane with my 'old' engine on it - assuming you get all the logs and the signoffs? It's still a Comanche 260C with the normally aspirated engine - the Type Certificate is the same I think -

Thoughts?

 

[comanchepilot]

What's the price risk on the sell side?

I think there would be line out the door for a Comanche 260C - normally aspirated priced as a run out - right around $60k.

There are not many 260C's for sale ever - the only ones that remain for sale are the ones priced over $100k which is crack smokin' jones territory.

You could wholesale the flying airplane for $50k - and have a line out the door and still save $10k and get a turbo in the process . . ..

 

[wabower]

We do these deals frequently on turbine-powered planes, but mid-time King Air engines still have 1800 hours before the overhaul interval so the logic for the swap is easier to digest than on pistons. My concern with doing it on your plane is that all of the "oopsies" (like exhaust system rebuilds or cracks that couldn't be seen when the engine was bolted up, control cables, sheet-metal and engine mount damage, you name it) can all raise their head on one or both planes and bust the budget in a NYM.

QUOTE=comanchepilot;1158879]As many of you know - I own a 260C Piper Comanche.

Lets assume that I love the way my airplane is set up avionics wise. Sooner or later I will need an new/rebuilt motor.

Lets say there is identical year Turbo 260C Comanche available for sale. With 350 hours on the motor and turbos and new prop.

All of the accessories are the same.

Lets say I can buy this Turbo model, remove the firewall forward and simply drop in the 'new' mount, engine, prop and accessories. Yet - it is essentially a bolt on process. The only thing I keep from my existing airplane is that is engine mounted is the back up vacuum system - I must also remove the throttle, mixture, and rpm cables and housing itself, since the new engine has a manual waste gate.

An 'new specs' engine rebuild with a new prop in my airplane is about $45k assuming my crank is ok.

Lets assume I can buy this airplane for $75k. Lets assume the bolt on process is $10000 - since it on and on for 2 airplanes - total cost $85k.

then lets assume that a 1971 Comanche 260C with steam gauges and a run out engine can command somewhere around $60k in the marketplace.

Assuming that I now have a Turbo'd 260C with the killer avionics in my airframe - and since I have not removed anything from my airframe the 337's are still valid for the avionics - have I truly saved $20k? And gotten alot more utility out of my airframe with the turbo?

Is the FAA going to care any further of my assuming I get proper signoffs?

\Would this process affect the value of the airplane with my 'old' engine on it - assuming you get all the logs and the signoffs? It's still a Comanche 260C with the normally aspirated engine - the Type Certificate is the same I think -

Thoughts?[/QUOTE]

I think there would be line out the door for a Comanche 260C - normally aspirated priced as a run out - right around $60k.

There are not many 260C's for sale ever - the only ones that remain for sale are the ones priced over $100k which is crack smokin' jones territory.

You could wholesale the flying airplane for $50k - and have a line out the door and still save $10k and get a turbo in the process . . ..

 

[comanchepilot]

Thanks Wayne- such is true. . . . the bolt on bolt off is intended to avoid that . . . hopefully a good annual inspection catches all that anyway - you don't need to take anything off the 'new' engine since the engine mount bolts into the same holes . . . .on/off - replace the fuel lines / cables and off you go.

At least thats the idea. Maybe I should call . . .

We do these deals frequently on turbine-powered planes, but mid-time King Air engines still have 1800 hours before the overhaul interval so the logic for the swap is easier to digest than on pistons. My concern with doing it on your plane is that all of the "oopsies" (like exhaust system rebuilds or cracks that couldn't be seen when the engine was bolted up, control cables, sheet-metal and engine mount damage, you name it) can all raise their head on one or both planes and bust the budget in a NYM.

 

[wabower]

Agreed. The guy at the shop will probably be able to lay it out better and quantify some of the costs you may need to consider. I was at the shop yesterday watching the replacement of a low-time T-Lyc on an Aztec. During a routine oil change the filter was full of whiskers. Turned out the cam had died. $$$$.

Thanks Wayne- such is true. . . . the bolt on bolt off is intended to avoid that . . . hopefully a good annual inspection catches all that anyway - you don't need to take anything off the 'new' engine since the engine mount bolts into the same holes . . . .on/off - replace the fuel lines / cables and off you go.

At least thats the idea. Maybe I should call . . .

 

[Sam D]

Thanks Wayne- such is true. . . . the bolt on bolt off is intended to avoid that . . . hopefully a good annual inspection catches all that anyway - you don't need to take anything off the 'new' engine since the engine mount bolts into the same holes . . . .on/off - replace the fuel lines / cables and off you go.

At least thats the idea. Maybe I should call . . .

Why not call the run-out engine "newly installed"? Then add a fancy new acronym in the ad: 0 TSNI.

 

[Ted]

We'd had similar ideas with the 310 - find one that had the Riley Turbostream (TIO-540 Lycomings on it) and try to convert that over. In the end, we figured that the potential legal issues would be too great to expensive to attempt to overcome.

Don't they still sell the turbo STC for Comanches? Why not just put one of those on new?

 

[JHW]

We'd had similar ideas with the 310 - find one that had the Riley Turbostream (TIO-540 Lycomings on it) and try to convert that over. In the end, we figured that the potential legal issues would be too great to expensive to attempt to overcome.

you'd be better off just buying a BE56 baron if you want a light twin that'll make contrails

 

[comanchepilot]

I want to avoid turbocharging - I've operated a turbo normalized system before - successfully - and want to avoid pressurization of the cylinders above sea level design.

Hmm - legal issues? Didn't think about those.

 

[comanchepilot]

When you say new prop, do you mean really new or overhauled?

New as in installed on the turbocharged engine . . . . 600hrs.

 

[John221us]

You are unlikely to recoup sales tax on the subsequent sale. That could eat up another $6k.

 

[comanchepilot]

You are unlikely to recoup sales tax on the subsequent sale. That could eat up another $6k.

Depends where we buy the airplane and who buys it . . .

I would prob find someone in a state like South Carolina do the work - using a corporate entity to acquire the airplane - $300 max sales tax. . .

 

[SCCutler]

Never say never; I think it is very possible you could do this, as long as you found the right donor plane. I have occasionally thought the same thing when I'd see a Bonanza for sale with marginal avionics, interior, etc. and a low-time engine. Buy, swaperoo, my plane has a new lease on life and the donor plane is still a flyer.

Makes more sense with a Comanche C; these hold value amazingly. One of the prettiest planes ever, and roomy, too.

 

[wabower]

Really? Are you prepared to undertake such a project from that distance?

Depends where we buy the airplane and who buys it . . .

I would prob find someone in a state like South Carolina do the work - using a corporate entity to acquire the airplane - $300 max sales tax. . .

 

[comanchepilot]

Really? Are you prepared to undertake such a project from that distance?

We own a house in South Carolina . . .

And just because the transaction is based there who says the work needs to be done there?

 

[AdamZ]

Don't forget the sales tax. What is it in CA 7.5% plus some areas are higher so thats a minimum of $5,600 that you need to deduct from the 20K savings.

 

[SCCutler]

Don't forget the sales tax. What is it in CA 7.5% plus some areas are higher so thats a minimum of $5,600 that you need to deduct from the 20K savings.

Bah.

Do it all in Texas, no sales tax on occasional sales.

 

[weilke]

I know of a 71 260-C TC that was wrecked in a runway overrun. The engine at minimum needs a teardown and the wings are shot, but the owner may be interested to sell the powerplant.

 

[poadeleted20]

Have you done the research to find out what's involved in the "proper signoffs"? This major alteration will require approval on a 337 via either an STC or a field approval, and the cost of the field approval process (DER, flight testing, etc.) will stagger you. So, is there an STC for this installation? If not, it's probably a nonstarter.

 

[Ted]

you'd be better off just buying a BE56 baron if you want a light twin that'll make contrails

So I can have unsupported, orphan engines that are lucky to make their 1200 hour TBO instead of engines that are supported and make their 1800 hour TBO easily?

Actually if I do anything to get into contrail land I'll just add turbos to these 520s, but I think I'll stick to what I've got. Can't fly that hgih with the dogs or baby unpressurized anyway. I'd rather just try to squeeze a few more knots out of this bird.

 

[flyingron]

Ron, it depends on just what the type certificate provides for. Not all engine changes are major alterations. There is information on the PA-24 type certificate for an optional IO-540 with RayJay turbos on it. If you follow the guidance in the referenced piper drawings on the installation, it can be done with just a log book entry.

If however, the engine installation is not provided for on the TC, then yes, you need either an STC or to get a field approval.

 

[wabower]

You just said so. Or does "find someone in SC to do the work" mean something else in lawyer-talk?

We own a house in South Carolina . . .

And just because the transaction is based there who says the work needs to be done there?

 

[bnt83]

A few thoughts...


#1 Is there already an STC?
#2 Cowl fit?
#3 Placard Changes?
#4 Airspeed markings?
#5 TIT Gauge?
#6 Oil Cooler the same p/n? Mounting location?
#7 TCDS shows different boost pumps used between the turbo & N/A versions
#8 Oil filter adapter differences?
#9 Different Flight manuals

S/N 24-4783, and 24-4804 through 24-5034 (with normally aspirated engine):
9 (b), 9(d) or 9(g), (9e), 109(g), 113, 114(d), 120(a) or 120(c), 201(d), 202(b), 205, 206(a), 302(a), 305(c), 401(bo), 603, 617(a), and 410(bz).

S/N 24-4783, and 24-4804 through 24-5034 (with turbocharged engine):
9(b), 9(f) or 9(h), 9(e), 109(h), 115, 120(b), 121(a), 122(a), 201(d), 202(b), 205, 206(a), 124, 302(a), 305(c), 401(bp), 603, 616(a), 617(a), and 401(bz).


Rayjay estimates 60-80 hours to convert an N/A to turbo. I think you'll be double that on two airplanes.

 

[EdFred]

It may be easier to swap panels as opposed to engines.

 

[Skylane81E]

It isn't as easy as you think it should be, unless the TCDS allows for a factor turbo engine on your S/N or there is an STC for that engine/turbo/prop configuration you are looking at a field approval.


I am with Ed, swapping everything good from your airframe to the turbo would likely be the "better" option.

 

[weilke]

It isn't as easy as you think it should be, unless the TCDS allows for a factor turbo engine on your S/N or there is an STC for that engine/turbo/prop configuration you are looking at a field approval.

As I understand it, the factory used what is basically the Rajay STC but incorporated everything into the TCDS as an optional engine:

Item 109

IO-540-R1A5 (Turbocharged - Items 122(a) required)
installed per Piper Dwg. 27137

Item 122(a)


Turbocharger
Rayjay
No. RJ0080-102
(2 required when Item 109(h) is installed)


This would suggest that if one has 'drawing 27137', 2 Rayjays and all the other parts called out in the parts-list, they could convert an engine. I dont know if the current owner of the Rayjay STC licenses it for new installations, but that would be the other option. 60-80hrs sounds like a lot of work.

I'll ask the owner of the wrecked factory 260C-TC to have a look at the books.

 

[poadeleted20]

It is still a major alteration requiring documentation on a 337 and an IA's signature. The only difference would be that you would reference the type certificate rather than an STC as the approved data. However, the end product would have to be identical to that TC, not just taking an engine off a Turbo Comanche and bolting it on a regular PA-24.

 

[bnt83]

It is still a major alteration requiring documentation on a 337 and an IA's signature. The only difference would be that you would reference the type certificate rather than an STC as the approved data. However, the end product would have to be identical to that TC, not just taking an engine off a Turbo Comanche and bolting it on a regular PA-24.

Thats the way I see it. This will involve more airframe stuff than bolt on/off items and of course the the placards and flight manual, then weigh both airplanes etc etc etc. This work will $add$ up in a hurry.

 

[bnt83]

All assuming they don't find major discrepancies while performing the alteration.

 

[comanchepilot]

It isn't as easy as you think it should be, unless the TCDS allows for a factor turbo engine on your S/N or there is an STC for that engine/turbo/prop configuration you are looking at a field approval.


I am with Ed, swapping everything good from your airframe to the turbo would likely be the "better" option.

It is much much more costly to move avionics than it is to bolt an engine, prop, accessories onto the a firewall . . . .

 

[Skylane81E]

It is much much more costly to move avionics than it is to bolt an engine, prop, accessories onto the a firewall . . . .

Only if all you have to do is bolt/unbolt the respective firewall forward assemblies.

If you can get your hands on the specified drawings you might be able to pull it off.

 

[comanchepilot]

The turbo engine is IO540-N1A5, the NA engine is IO540-D1A5 . . .. though some NA airplanes have the N1A5 without the turbo system . . . like mine. So I already have factory paperwork with the N1A5 . . .

Paperwork is simple - esp if its a 337 with a TDCS reference . . . I'm not worried about paperwork. Paperwork is what I do for a living.

This is exploratory and it does seems like there is very little in the way except condition - and paperwork. Some may see that as a huge challenge - I was more worried about stumbling blocks that are not obvious . . . .

 

[comanchepilot]

All assuming they don't find major discrepancies while performing the alteration.

thats always the case . . . . a good inspection from a good Comanche mech would resolve that upfront - and I happen to know two locally . . .

 

[wabower]

Most of those install estimates are based on shops that know what they're doing and have some in-house experience. It's not unusual to see 50%+ labor variances.

A few thoughts...


#1 Is there already an STC?
#2 Cowl fit?
#3 Placard Changes?
#4 Airspeed markings?
#5 TIT Gauge?
#6 Oil Cooler the same p/n? Mounting location?
#7 TCDS shows different boost pumps used between the turbo & N/A versions
#8 Oil filter adapter differences?
#9 Different Flight manuals

S/N 24-4783, and 24-4804 through 24-5034 (with normally aspirated engine):
9 (b), 9(d) or 9(g), (9e), 109(g), 113, 114(d), 120(a) or 120(c), 201(d), 202(b), 205, 206(a), 302(a), 305(c), 401(bo), 603, 617(a), and 410(bz).

S/N 24-4783, and 24-4804 through 24-5034 (with turbocharged engine):
9(b), 9(f) or 9(h), 9(e), 109(h), 115, 120(b), 121(a), 122(a), 201(d), 202(b), 205, 206(a), 124, 302(a), 305(c), 401(bp), 603, 616(a), 617(a), and 401(bz).


Rayjay estimates 60-80 hours to convert an N/A to turbo. I think you'll be double that on two airplanes.

 

[EdFred]

It is much much more costly to move avionics than it is to bolt an engine, prop, accessories onto the a firewall . . . .

It is never as simples as that. Every project I have ever worked on turned out to be waaaaaaaaay more of an issue that originally planned.

 

[weilke]

It is still a major alteration requiring documentation on a 337 and an IA's signature. The only difference would be that you would reference the type certificate rather than an STC as the approved data. However, the end product would have to be identical to that TC, not just taking an engine off a Turbo Comanche and bolting it on a regular PA-24.

Earlier, the need for a DER was mentioned. I don't believe that that is the case for either executing a 337 based on either a TCDS and manufacturer drawing or a STC. An engine swap at the time of FWF overhaul may be a worthwhile endeavour, to do it otherwise soundss expensive. If one had the powerplant off a wreck, all the work like hunting down corroded clamps and overhauling engine mount and custom rayjay components can be done prior to taking the other engine off the firewall.

I loved that 260TC, still mad at the guy who wrecked it. Climbed to 16k without hot cylinders or anything. Spending money on upgrading a nice existing plane beats taking it with you into the grave.

 

[comanchepilot]

It is never as simples as that. Every project I have ever worked on turned out to be waaaaaaaaay more of an issue that originally planned.

I totally agree - there are always unanticipated issues . . . . I certainly am not the type to have rose colored glasses . . . .

 

[bnt83]

I totally agree - there are always unanticipated issues . . . . I certainly am not the type to have rose colored glasses . . . .

Just takes is

Don't plan on saving any money this way then there won't be any disappoinment.

 

[comanchepilot]

A few thoughts... [and answers]


#1 Is there already an STC?

Don't need one - TDCS references alternate engine.

#2 Cowl fit?

Tons of room - same cowl.

#3 Placard Changes?

small one adding turbo limits. Readily available - can even make one using strip printer.


#4 Airspeed markings?

Nope

#5 TIT Gauge?

Original aircraft did not have one. I intend to install a JPM700 at a min anyway - so will have it - I lean to TIT not EGT in most applications.

#6 Oil Cooler the same p/n? Mounting location?

Yep.

#7 TCDS shows different boost pumps used between the turbo & N/A versions -

mechanical fuel pump is on the ac case. The boost pump itself has different part numbers - so you swap them out. The electric pump is right on the firewall. Very simple replacement.

#8 Oil filter adapter differences

CH48110-1

#9 Different Flight manuals

Add page for the TIT operation.

All part of the 337. Will contain limitations for operation at 27" and 2400rpm when boosted. Also charts for engine operation when boosted, fuel flow, speeds etc.