View Full Version : Twin Comanche info needed, please
21st Dec 2009, 16:10
Any Twin-Comanche experts/owners out there in europe? A friend is interested in buying and is in need of a good pre-purchase inspection. Please PM me.
Sir George Cayley
21st Dec 2009, 21:37
Your, a'hem friend, likes a challenge then:ok:
21st Dec 2009, 21:52
Check your PM's
21st Dec 2009, 23:46
Thank you very much for the messages gentlemen!
Oh yes SGC - quite unafraid, handsome fellow, too :8
21st Dec 2009, 23:57
International Comanche Society (http://www.comancheflyer.com/NS/)
ComancheGear - Home (http://www.comanchegear.com/)
22nd Dec 2009, 00:22
Thanks Easy, should be something in there somewhere.
22nd Dec 2009, 13:00
...everything thereafter will be sooo easy! Good luck anyway! bm:ok:
22nd Dec 2009, 14:03
Nice twin with laminar wing, below MTOW 2000kg for Eurocontrol fees is one of the more important items. Don't buy one without a heavy prebuy inspection, it's not because they had a corrosion treatment in the factory that you can't find corrosion!! Don't get one without good fuel selectors.
Big Pistons Forever
22nd Dec 2009, 22:01
Don't get one without good fuel selectors.
Hands down the most efficent twin engine travelling machine but you want to do your homework particularly with respect to finding spares.
I can vouch for the quote. One of two engine failures I had in a twin was in a Twin Comanche after the fuel selector failed to switch from aux to main even though the cockpit selector was properly set. The result was a fuel starved engine just as I was intercepting the localizer.:uhoh:
23rd Dec 2009, 12:01
The Twin Comanche is the only viable option for the specific requirements, i.e. two engines and (relatively speaking!) acceptable cost. No need for blistering speed, massive load capacity or fancy avionics.
Interesting tip that, the fuel selectors I mean. Must have gotten your undivided attention when one started spluttering. Had a similar thing happen to me in a 310 once, mind you that was self-inflicted.
26th Dec 2009, 21:18
The fuel selectors are back in production. Make sure that the gear is in good shape. Contact the ICS for information and even better join the organisation. Make sure that the mechanic that pre buy your aircraft knows Comanches as there are things that are unique to this aircraft.
28th Dec 2009, 17:13
Thank you AC-DC, will be in touch.
28th Dec 2009, 17:34
Yes, the fuel selectors are back in production. But for the price they are selling you better buy a plane with good ones.
29th Dec 2009, 19:00
I have had one for 11 years. I bought it after a lifetime of flying military, airlines and regulator and it has been a fun part of my life.
Much drama about how dangerous it is and the mnay traing deaths it has had but they are not any reason not to get one.
Fly the recommend numbers is all you need to do and it is a delight except.............there are two aircraft that i believe are a challenge to land........A B-727 and the PA 30.
You will always make them safe but seldom like the greasers you can do with three radio altimeters in a B-747.
Mental arithmetic for the slowing mind is great also. 1 litre a minute and you have the GFC immediately without a FMC.
I have tip tanks and all the usual IFR stuff but the high end avionics are too expensive for me.
As for real IFR, I have done more real IFR (cloudy stuff) in my "Chariot" as I call her............than a lifetime in other aircraft..............and in Australia that means real NDB's.
It is just great and I love the way I can stay in the industry when there are so many prima donna jerks who do nothing but whinge.
Best wishes and go for it.:D:)
29th Dec 2009, 20:44
Don't know if you are an ICS member. If you are you can go into the ICS website (forums in the members section) and read about the technique or read the Comanche Flyer of 2-3 months ago where a shorter version of this descusion was published. If you are not a member then we will not be able to improve your landings :)
29th Dec 2009, 20:53
Yes, the fuel selectors are back in production. But for the price they
are selling you better buy a plane with good ones.
But as he buys the aircraft if they are bed he always can chop the price or not buy, I know of 3-4 twinComs. for sell, 2 of them should be in good condition while one I would buy without a pre-buy.
29th Dec 2009, 21:33
I've read some of the horror-stories Gunshy and I realise that the infamy is undeserved. If what I could unearth is true the aircraft was snapped up by many training-schools when it was released because it was relatively cheap to operate. Haven't had the pleasure of flying one yet and neither has my friend, but I understand that the 'Twinky' is a far cry from the somewhat agricultural Aztec, the only Piper twin I've had the pleasure of being rated on. You don't let a learner-driver loose in a early-model Porsche 911.
As regards the landings, surely one can simply apply the well-known technique applied by drivers of the quirky short-nose 310 everywhere, i.e. fly the thing until approximately above the threshhold, chop the power whilst hauling back on the pole and wait for the impact? ;)
The idea is to utilize the machine as a VFR transport, the steam-and-clockwork will be for the occasional puff of cloud not forseen by the weatherman.
29th Dec 2009, 22:25
I know of 3-4 twinComs. for sell, 2 of them should be in good condition while one I would buy without a pre-buy.
please let us know the 2 good ones and especially the third one you would buy without a prebuy.... We did not sign any deal yet :)
Always open to better options :D
PM us.... Thanks
31st Dec 2009, 07:46
The Twin Comanche is the best light twin ever built. There has been no other light twin that has the range, payload, and speed on that horsepower and fuel burn.
Having said that most are around 40 years old and that means 40 years of wear. Though nothing that good maintenance doesn't over come.
The Comanche has a strong well built airframe, but there are one or two areas that need good maintenance though probably no more so than other simlar types or aircraft. One area that needs to be well cared for is the undercarriage. It seems that some owners do scrimp on maintenance or some engineers don't fully comply with or understand the requirements for the 1000 hour undercarriage inspections.
The fuel selectors have been flagged as a potential problem area, they can be rebuilt/repaired though if there is too much corrosion they may need replacment. The main problem is the selectors also contain the fuel filter and water can collect in the fuel selector/filter. If this water is left there too long corrosion can result.
The big secret here is to do thorough fuel drains prior to flight but also after that last flight of the day drain the bowls on the selectors to attempt to drain any water that may have collected during flight. Surface tension can cause some water to be retained in the filter so it is absolutely essential to remove the fuel bowls every 50 hours as specified in the maintenance schedule (and I would suggest every 2 months) and remove and clean the filters and remove any retained droplets of water.
As with any 40 year old aircraft do expect to have teething troubles as a new owner. One issue with any peice of machinery is how much use it gets. Very often the niggling issues we experience with a piece of machinery is due to a lack of use. Things gum up and stop work through disuse. I believe that an aircraft needs to be flown at least every two weeks, even if it is only a couple of circuits.
PM me if you have specific questions.
31st Dec 2009, 07:50
Indeed, draining post flight makes much more sense than preflight. Unless you drain multiple gallons on preflight, you will not be sumping anything except for the filter bowl.
31st Dec 2009, 11:27
Only flown one of these things once, while considering doing a twin rating. (Circumstances changed; bought a house instead.)
Did a bit of upper air work, the usual stalls/turns and then some assymetric stuff..true eye opener.
As with any twin in this power range, don't expect the good engine to take you far if you are unfortunate enough to lose one on departure. We were at least 500lbs below gross, and with the critical engine feathered and everything cleaned up, the climb rate was a good 80-100 fpm.
Every one of the circuits I flew (about 7 landings in all) resulted in a smooth landing. As with a Mooney, with its all-flying tailplane, trimming through the flare seems to help quite a lot in achieving a passable touchdown.
31st Dec 2009, 14:17
I own a quarter share in a PA30. In fact it`s the one that was previously owned by Sir Douglas Bader. So, if he can land it without legs, it shouldn`t be as difficult as some seem to think :)
Lovely airplane with very simple, reliable engines. I heard the stories about the landings too, but I find the PA30 at least as easy to land as the seneca. Not much difference.
The ICS is a very good place to get information. They have a guy there that is the absolute gear-guru for the PA30.
Have fun with it!
1st Jan 2010, 10:08
All the best for this new year to you all!
Thanks for all the replies! It is clear that the fuel system needs good looking at, as does the gear - by the way, we were told the gear needed a 500-hourly overhaul, not 1000? Lindberg put together a comparison chart between Beech Travelair, Piper Seminole, a Dutchess, some-or-other thing called a Cougar, and the Twinky. Compared load, current price, speed, range, fuel burn, etc. The Twinky really does seem way ahead of the pack. Furthermore, all the pilot reports seem to indicate that all the rest were bolted together purely as trainers whereas the comanche would appear to be in a Mooney-esque class of its' own. Hmm, going to be interesting to fly the thing.
To the poster who mentioned single-engine performance - we're not labouring under any illusions regarding engine-out scenarios whatsoever. You lose one on rotation or in the initial climb, you're landing, agree 100%. The advantage of this little airplane over all the singles is that you have a fighting chance when out over hostile terrain, if loaded within reason.
1st Jan 2010, 10:27
Lindberg put together a comparison chart between Beech Travelair, Piper Seminole, a Dutchess, some-or-other thing called a Cougar, and the Twinky. Compared load, current price, speed, range, fuel burn, etc. The Twinky really does seem way ahead of the pack. Furthermore, all the pilot reports seem to indicate that all the rest were bolted together purely as trainers whereas the comanche would appear to be in a Mooney-esque class of its' own. Hmm, going to be interesting to fly the thing.
I (and my current co-owners) flew a Mooney 201 for years but decided that the mission profile was such that an economical twin would be preferable. We did the utility comparisons just like you, and also concluded that the Twin Com was ahead, so we went for it. But the unexpected bonus was that it really does fly beautifully.
I think the landing issues come from the nose-high ground attitude. For any landing aircraft, there's a window between the limits of stall AoA and ground attitude (to avoid banging the nosewheel first). For the Twin Com, that window is narrow. Full flap doesn't help (reduces stall AoA). The vortex generators do.
You can get lucky with landing. Our aircraft was flown by a prospective (and now current) Twin Com owner, with a great deal of light twin experience. His words after his first landing were "You know I really don't see why everyone makes such a fuss about landing the Twin Com. It seems just fine to me." After his second landing, his words were "Oh... Sorry ..." We parked up and closed the baggage hatch which had popped open with the impact.
1st Jan 2010, 10:33
The Cougar is Grumman AA7, makers of the very appealing Traveler/Cheetah and Tiger singles.
Flown the singles (Nice.); never the twin, though one of my instructors did mention he thought the AA7 a great a/c to do a twin rating on.
Your research/presentation indicates what I often thought, based on reports. The PA30 (39 if you can score one!) was above-average build quality. Intended for discerning private owners, probably more so than as a flying school/aero club aircraft.
I sure found it very pleasant to fly. Nicely appointed.
2nd Jan 2010, 08:35
To put the Twin Comanches' single engine performance into perspective, take a look at the following figures I got off the net. I acknowledge that some of the figures may vary slightly from some manuals but never the less will be close enough to give a good comparision.
PA30 260 fpm
PA31-300 Navajo 270 fpm
PA34 Seneca II 235 fpm
PA44 Seminole 180 fpm
BE76 Duchess 235 fpm
BE58 Baron 390 fpm
Cessna 402 225 fpm
DA 42 Twinstar 160 fpm
While none, except perhaps the Baron, have startling single engine performance I think you will agree the Twin Comanche compares pretty well.
The PA30 (39 if you can score one!)
Well actually the PA30 outperfoms the PA39. Long story short, counter rotating engines are not as efiicient as non counter rotating engines. It's to do with the slip stream from the props and the flow over/around the airframe. Apparently Piper increased the power on the C/R Navajo from 300 to 315 to get the same performance as the non C/R Navajo.
The only advantage that the PA39 has in my eyes is the more modern panel layout and you can be that in the PA30C anyway.
Apparently the PA30B was be best performer however my choice would be the PA30C to get the modern layout, but even then there are STC's to change the old layout to the new layout.
2nd Jan 2010, 15:14
KeepItStraight, also keep in mind that my PA39 has a re-inforced tail spar. They did that after the elevator flutter test ... YouTube - PA-30 Twin Comanche Tail Flutter Test (http://www.youtube.com/watch?v=wAiOcPVXW0c)
2nd Jan 2010, 21:50
also keep in mind that my PA39 has a re-inforced tail spar
Your point being Sternone?
NASA were doing the testing for their own purposes not the prove any weakness in the design.
The flutter in the video was deliberately set up by introducing extreme conditions.
This flutter would not occur under any normal or most abnormal circumstances. It is very unlikley that any pilot would encounter it especially if the aircraft has been maintained properly and the trim tab mechanism is in good condition.
To my knowledge there has never been an accident due to tail plane flutter.
My point is your stronger tailplane is nice to have but is not required.
2nd Jan 2010, 23:37
Messrs Bookworm and Tarq, glad to hear our research confirmed. Will report back when Lindberg and I have had the chance to get to grips with the machine. Will be about 3 to 4 more weeks, seeing as there's a bit of company-aviating to be committed in the interim.
Keepitstraight, the one light piston that would stand out if it were included would be the C404. About 350 feet+ on one, at that's at less-than-ideal temps on the African plateau. Lovely bit of kit, really miss it. And aren't the numbers on that Diamond-thingy a bit shocking? You'd think they'd build something capable of performance on a par with the dinosours, at least, as opposed to even worse!
The Youtube excerpt posted by Sternone makes for sobering viewing. Definately induced through exceptional circumstances then, was it? I remember a glider landing with the aft fuselage a splintered pulp due to a flutter induced in sudden turbulence during high-speed flight. The pilot was understandably reluctant to exit via parachute and therefore, having established some semblance of control at very slow speed, managed to land safely.
3rd Jan 2010, 01:05
Don't put any multi-thousand-pound stock in my "confirmation"; I like the aircraft and have flown it, my knowledge aside from that is anecdotal and from books/mags.
That said, go ahead and buy one!:8
3rd Jan 2010, 04:23
aren't the numbers on that Diamond-thingy a bit shocking?
Yes, but not surprising considering the aircrafts weight and the power of the engines. I could not believe the estimated factory performance figures when the DA42 was announced. 184 KTAS at 12,500 and a single engine RoC of 500 fpm.
All of the performance figures (Take Off dist, RoC, Cruise, Landing dist) seemed to be a bit far fetched for two 135 HP engines lugging around 1700kg. In the event the actual AUW ended up at 1785 kg. The specs now give a 156 KTAS at 10,000 and the S/E RoC of 160 fpm.
Compared to the original factory estimates the take off distance increased by 47%, two engine RoC reduced by 38%, S/E Roc reduced by 68%, cruise speed down by 14%, landing distance up by 42%. How did they get the estimated figures so wrong?
I smile when I see and hear people going on about how good the DA42 is. It is certainly no quantum leap forward from aircraft that are 40 years old.
Certainly the Comanche has more power but the plastic wonder has an empty weight nearly 20% more, carries 17% less payload, has 85% less luggage capacity and flies 8% slower.
3rd Jan 2010, 07:30
My point is that there is another difference which you didn't point out that the PA39 has a reinforced spar in the tail.
May I remind you that with the Nasa testing the tail didn't brake or fall off :}
About the DA42, I flew the first generation and the 2.0 engines. Compared to the twinkie I have a feeling that I need twice as much the runway. When you apply power on the twinkie you feel the engines pushing you to your seats, that's a good sign. Never had that with the DA42, in fact during my takeoff roll I was wondering when this plane was going to fly.
Diamond first numbers in their brochure was a DA42 with thielert 1.7 engines that would be a 200+KTAS plane. :ugh:
Der absolute Hammer
3rd Jan 2010, 08:03
Used to be a member here...and still fly TCs fairly regularily.
Useful site I used when I wanted to fly a TC with TTs around the world. Never did though.
It's a wonderful machine that has got a bad reputation primarily for two reasons.
It is a favourite training machine because it is cheap to buy and cheap to fly.
But...under certain conditions of altitude demonstration, Vmca can be the same or less than Vs. This has led to spin situations in the hands of relatively inexperienced pilots, which in a twin is not a good idea.
Landings are easy enough if you stick to the manufacturers bug speeds which are aleady worked out in the TC handbook for MLW. If you give the machine the usual five knots for mummsie and the kids you will come in too fast and the airraft can very easily wheelbarrow. The nosewheel is a potential weak point in the hands of a Ferrari pilot.
From a maintenance point of view, watch out for the fuel tanks. They are bladder tanks and sitting around doing nothing will crack them unless they have been left full of fuel. Fuel selectors have been covered. Nosewheel gear and undercarriage/spar need checking-especially if machine used for training, whihc it almost certainly at some time will have been. There are various different combinations of gear selectors and electric or manual flap. Make sure you know what you are buying with this. Some of the gear warning lights bulbs can be unusual.
Carpets and under floor rot are sometmes a problem, though not only in Pipers and check on the quality of any recent paint job done perhaps only as a cosmetic. The airplane history-where it has lived-is important also. Hot and dry or cold and wet.
Outside of the Navion, which is now really too old, I do not think there is a better or more fun machine with TTs for long range world cruising in safety and comfort for two people. I don't think en route maintenance would be much of a problem although you would possibly want a few spares holding yourself as you came across the stuff available. Incidentally-this is only hearsay, I would avoid anything fancy like a turbo charged TC. There was though a normal aspirated for sale recently in South Africa where they are still quite popular,.
I envy you..happy flying..because that is still what the TC is-a pilot aircraft.
4th Jan 2010, 07:46
Thanks to all giving us good advices to the plane. It looks there are no questions about the flying qualities of the plane (ecxept the landings). As I own a singele engine aircraft already, I am not copletely new to the business, but this is a historic airplane and so maintenance is easy. I can do owner maintenance according an approved programm from the authorities. How is this on the twin comanche? Is it an annex II aircraft? If yes, do I have a choice between the relatively new maintenance programm (CAMO) or the old 'annual check and TBO thing'? I am talking about Europe... Even we have JAA & EASA, there are differences in the countries.... Any good advice for registrating the aircraft in a special country? Or is N-reg an option in Europe? :hmm:
Thanks for your advices.... :ok:
4th Jan 2010, 08:14
Is it an annex II aircraft?
No. Close, but it didn't quite make the cut.
F.Lee Bailey "bullet" conversion for the TC :
Palm Beach Roamer, Inc. ( Aircraft Shopper Online, Aircraft Sales, Aircraft for Sale ) (http://www.aso.com/seller/6038/bbullet/main.htm)
29th Jan 2010, 12:42
How did things work out?
Was the twinco in good condition?
29th Jan 2010, 22:20
Lindberg was unable to view the aircraft as a short-notice trip came up for him, unfortunately, but I got to have a peak along with the very capable gentleman from Biggin who did the pre-buy. The latter gent will be writing up a list of snags, what stuck in my mind were the very stiff throttle- and mixture levers (no need for the friction-nut at all!); a row of corroded rivets in the exhaust-stain of one donkey (the other side has clearly already been re-riveted in the past; very loose fuel selectors (!!!); soggy carpet in the cabin (although, to be fair, the aircraft had been washed inside and out before we got there); some water weeping from underneath the fairings atop of the wings aft of the engines, minor corrosion in a couple of places; paint poor. Engines seem in good nick, props are good, ditto gear, cockpit ok. Mixed feelings. Waiting for Lindberg's input.
A scary thought is the rumour that the regulators want to put in place a law limiting engines to a twenty-year lifespan, only. Thoughts on this, gentlemen?
30th Jan 2010, 15:07
Do you have asking price and Total times on engines/props/airframe ? DH ?
30th Jan 2010, 22:18
Sternone, please check your p.m.