Robtck

How much time should someone fly a twin trainer before flying a P-38? Is it better to build a twin boom trainer over a Twin-Air? I know I can fly any single, but a twin is a hole new ball game. I'm planning on building a Z P-38 or P-61.

William Robison

My Feedback: (3)

BC:

Ideally, you'll stay with the twin trainer until you can handle either engine out without even raising an eyebrow.

But since that will never happen, get all the stick time you can with the trainer while you build the P-61. Save the P-38 until you have a lot of time on the '61 - it's a somewhat intermediate plane between the trainer and the P-38.

Bill.

kram-RCU

I'm not sure all that engine out experience on "normal" twin is gonna help if it happens on a P-38. It would help to gain a lot of experience tuning engines, etc., to make sure an engine doesn't go out.

You force me to repeat my oft-repeated belief: P-38's aren't that hard to fly if you keep both engines running. I believe it a far wiser time investment making sure both engines run than to worry and train for "engine-out." Sure, I spend time on the simulator and my trainers practicing, but if I have an unplanned engine-out on a P-38, I think there's at least a 50% chance I'll lose the plane. So I spend a lot of time and effort minimizing the probability it'll happen. That's a trait pretty common to twin flyers everywhere, as Bill alluded to above.

I had a good friend in the flight club here who moved out to CA. We were chatting about differences in flight clubs, fields, attitudes, etc, and he mentioned that "the P-38 flyers in California are just like you." I asked what he meant and he said: "Oh, they usually come out to the field, stand on their heads for two hours tuning their engines, then pack up and go home."

I would go ahead and start on the Z-38...if you don't have any more free time than I do, it's a labor of love that'll take you a coupla years anyway. By that time, you'll be a twin ace.

mt

William Robison

My Feedback: (3)

MarkT:

Definite agreement on the engine reliability issue. And agreement on the difficulty of saving a 1/2 dead P-38.

But it's just like general aviation. The majority of reported accidents are fliers with less than 100 hours.

The same carries through to our little planes, that's why I suggested he get all the stick time he can with the easier flying plane, and then go to the P-61 as an intermediate step. Save the P-38s and B-25s for later.

Bill.

Robtck

Thanks for the info. This is some good information. I've had the Z P-61 plans for about eight years. This winter I will start building it. In the mean time, I will kit bash a big stick 60 into a twin boom trainer. If I build the P-61 then the P-38. I figure the P-38 will be ready to fly in about four years.

flying2bill

My Feedback: (2)

I did a similar thing with an old Midwest giant sweet and low wing I had, I used the basic measurements from the Ziroli (span, length, engine spacing ect) and just started cutting and glueing. Still working out the bugs. I started with all new eqipment (except the engines) and so far have had the following problems broken wire on ignition module (neccessitating a 1 engine landing on maiden flight), steering servo failure, aileron servo failure (not the same brand). so far no major damage.

guylem

My Feedback: (2)

I have now flown 4 twins. The first one was a German Twin Comanche which flew very well until an engine died due to glow plug failure after lift off. The second one was the Twinstar which I flew on a Futaba 6XA, always fearing an engine failure which never occured. I have since bought a Futaba 9 channel system which I now use on the Twinstar, and also a Twinair and a GP P-38. I have programmed the TX so that I can bring the left engine to idle by bringing switch E to the down position while retaining full throttle control on the right engine. Conversely, putting switch G in the down position will bring the right engine to idle. I am thus able to simulate engine failures at will and observe the results. Here are some of my findings. An engine failure on either side while at low speed and high angle of attack with over 75% throttle will always result in a spin so it is a good idea to let the airspeed build up before climbing out after take off. The Twinstar and the Twinair can be kept flying on either engine i.e. turns in either direction can be performed, though they are more difficult to control when the right engine has lost power. Throttling the left engine to about 70% and bringing the nose down a bit to keep the airspeed up helps a lot. Steep climbs and loss of airspeed with the right engine out has usually resulted in a spin. The best way out of these spins is to throttle back and neutralize the controls followed by a gentle opening of the throttle and gentle pull up after airspeed has been regained. One thus requires some altitude to recover. As for the Great Planes P-38, I have found that I can keep it under control with the left egine out but that it inevitably goes into a spin with the right engine out regardless of the direction of turn (mine is equipped with two .25's and 9.5x6 props). I feel that the problem with this aircraft is that the engines are farther out from the airplane's centerline than on single fuselage twins and the resulting asymmetric thrust is too much for the size of the rudders. The best advice I can offer after these experiments is to keep the airspeed fairly high, keep the airplane sufficiently close so that you will be able to identify unplanned manoeuvres, namely direction of spin, that will hopefully tell you which engine is out and let you compensate with rudder. It also helps a lot if you are the only one in the air while flying a twin so that changes in sound can be easier to detect and warn of impending difficulties.