warbirdz1

Gentlemen.....Its occured to me that theres lots to be said about how to handle an engine failure while flying a" Twin"......What I would like to do is collect some data from all of the "Twin" flyers out there that have" personally" had their "Twin" lose an engine........give details about what happened whether the airplane was lost ,slightly damaged or came "home" safely......this way we can come with a nice list of dues and don'ts to help all of us builders/flyers.....I'll try to give some basic guidelines to go by....we can modify from your input as we go along if needed.....Give the name of aircraft , weight and wing loading if known(W/L is an imp factor).....a picture if available.....engine type........ gyro/no gyro.........the profile of flight(cruise, T/O landing..etc)......which engine failed....what the aircraft did @ eng. failure(Yaw, go inverted,pitch up..Etc)......how you (Pilot) responded to the engine failure("paniced",reduced throttle, added rt rudder, added Lt aileron ,etc)...how the airplane responded to your initial inputs......what was the sequence of events after engine failure(make a landing on the runway,forced landing elsewhere.....lost airplane, spin in, etc)....and what inputs to the Tx helped/hindered ..the recovery after the engine failure.....what one thing did you learn about "Twins" from the experience......Bill...

warbirdz1

Ok....I'll get the ball rolling...most of you know the story about B-25 #1.....so I'll make it short . "Z" B-25...102" WS....37 lbs....52 oz WL............on a rt shallow climbing turn @ 400 ft...# 1 eng failed and it was inverted Immediately(maybe sooner)......reduced power and continued roll back to straight and level.........pushed nose down to gain airspeed.........airplane became virtually non visible due to brush, etc.....bellied it in best I could slightly holding some up elevator when I "Guessed" it was close to the ground......Plane was severely damaged due to landing on a rockpile.......Lesson learned: when flying a "Twin"..make every effort to fly at a field with clear areas and good bailout places....not at a field where the only place to land is the runway........Bill....

FLYBOY

My Feedback: (11)

When flying a twin, there is a number on the full scale called Vmc. It is the speed at which you loose directional controll with one engine running and full power on the other. There is more to it, but we will leave it at that for now. A model has the same thing but you don't have an air speed indicator. Basically, if one quits and you are slow, you are foced to either shut the other one down, or it will cause the plane to loose directional control, resulting in a spin.

If you are fast and the engine quits, you may have to power back a little, but not all the way. Keep your speed up and land. Don't go to full power on the engine running if you are slow. Be prepared that if one quits, you are going to basically shut the other one down to prevent loss of controll. You can get some use out of the other if you are fast, but it is better on a model not to count on it. The more you fly it, the more comfortable you will get with it and your procedures can change.

Would be cool to have the throttles seperated so you can practice it like practicing autos on a heli. Hit the switch and have one cut back to idle. Just a though. Do it high, and always leave yourself an out.

Tmoth4

My Feedback: (1)

I have a 100" Cessna Bobcat with two 25cc gas engines that weighs about 30#. One time I was flying along happily and one engine suddenly quit. I was up fairly high but going downwind in the overfly zone, headed out. There was no way I could tell which engine quit, so the rule of not turning into the dead engine was useless. I throttled down some, turned back to the field and the plane fell right into a spin. I immediately chopped the throttle and it came out of the spin right away. It was still hard to tell which engine quit and I didn't feel like I wanted to dare apply any throttle to the good engine. Fortunately I had enough altitude to nurse it back to the field like a deadstick, and it set down in the tall weeds just before the runway threshold with no damage (lucky!). The reason the engine quit is because one of the fuel tank overflow tubes got jammed in the flywheel. Now I'm more careful about tubes hanging inside cowls. Also, I'm glad I practiced spins and spin recovery with other planes.

Jim

FLYBOY

My Feedback: (11)

Geez, that sounds nasty Jim. My friend flying his duelist was flying when one quit. He went to full throttle. She started spinning fast. I was yelling "shut it off, shut it off." He finally did. He recovered from the spin almost perfectly lined up on the runway. Can you say lucky!!!!

I took my full scale Airline Transport ride in a Turbo Commander. The only plane I have ever been taught to shut one down and do steep turns into the dead engine. You gotta love huge rudders.

JimTrainor

RealFlight includes a simulation of the Hobbico Twinstar.
You can kill one or both of the engines in the simulator. It behaves similar to what is described in the previous posts - i.e. too much throttle, applied too quickly, at the wrong time, will cause all sorts of wild spins and gyrations.

TexasAirBoss

My Feedback: (22)

I'll get the picture up later. I flew a 68" Beech King Air 1900 for 11 years before selling it in late 2001. The plane had somewhere in the neigborhood of 1500 flights on it. I would estimate about 80 or so engine failures. There is a significant difference between loosing the left engine and the right engine. Some days loosing an engine was a total non-event. Other days it was a hair raising experience that left me shaking. I don't know what the difference was. Density altitude maybe, I can't say.
Even if someone builds the exact model that you are building, thier experence may differ greatly from what might happen to you.
I could never turn toward the good engine without reducing power. If I turned toward the dead engine, then I had to reduce power to return to level.
People would ask me which engine had died. My response was always, " I don't know, look at my hands and you tell me!" My point is this, you will automatically and instantly compensate for an engine failure. It just happens. The tricky part is trying to figure out which way you can turn without reducing power, particularly if you tend to fly around on the deck like me. Many times I would watch my plane get smaller and smaller as it flew away from me. I would have the sticks all the way over and there she flew straight away. Many times I thought, this ain't working! Do something, something different, anything but this. Relax the rudder!!!! Not all the way, just a little and it will turn back. And believe me, the time will come when you say to yourself, "this ain't working!"
I don't know why I had the succes that I did. I don't have the best hands and I don't have the best eyes either. The first two or three years I had the model, I flew it high enough that loosing an engine only meant that I might have to extend a glide slightly with the remaining engine. I only made breif low passes and then returned to altitude. My heart was always racing when I landed, the plane was an absolute thrill!
We lost a flying site in the woods and joined an AMA club with ahuge wide open field. No obsticals at all to hit. It seemed boring at first , so the twin started down to the deck. I loved flying it around low. I could generally tell if the engines were singing along together, and if they weren't then I would climb up or land. This is the time I started loosing engines down low, say less then twenty feet high. And this is the time I really learned what it was to fly one one engine. No altitude to exchange for speed, the plane would slow very close to Vmc. There were a couple of failures on short final , low and slow with full flaps. I couldn't add power without rolling over, and I couldn't bring up the flaps without landing short of the runway and into a plowed feild. Both times resulted in ripping one of the main landing gear out of the wing. I went right back to making those slow flat approaches anyway, they look so cool. But they can bite you. Anyway, if an idiot like me can have succes flying twins, believe me, anyone can!!

Tmoth4

My Feedback: (1)

FLYBOY,
It must have been really scary to shut down a perfectly good engine while you're in the plane!

Twins are awesome! After the first engine is idling and you get the second engine running the sound is incredible. It gives me a thrill every time. I put off building a twin for years because I didn't trust the reliability of glow engines. When I was into gas engines for a few years I finally built the Cessna. The gas engines really are very reliable and rarely quit once they're running. The only time out of many flights that I had a flameout was because of the mechanical problem described above.

The Cessna Bobcat flies great but takeoffs are a little hairy sometimes. The combination of twin engines, taildragger configuration, and a rudder that is blanked out when the tail is low all contribute to an interesting takeoff roll. My next twin project is a Bf 110. One of the reasons I picked it (besides being a cool German warbird) is because of the twin fins/rudders which are always in the airstream and I'm hoping the takeoffs will be a little less exciting.

Jim

mucksmear

Great idea for a thread gents!

I think most of us recognise that different twins have different recovery characteristics, or lack thereof!

Here's my limited experience, posted in part from my site:

Modified Duellist:
Span: 78"
Wt: 10.75 lbs. dry
W/L: 29 oz/sq.ft.
Engines: O.S. 46sfp
Props: 3-bladed Zinger 10 x 7.5
twin rudders (similar to Bf-110)

1) Port engine died on final (about 50' from runway) when engines brought to idle. No noticeable change in flight. Landed without incident

2) Port engine died on the downwind leg of the right-hand pattern, aprox 20' altitude, but went un-noticed untill after the right turn on to base and final (was setting up for a leisurly flyby, so not as slow as for a landing approach). After a gradual throttle-up to full with no ill effects, the model was nervously turned right (away from the pits area, but towards the dead engine) and back to the downwind leg. At full throttle, was able to climb back up to a decent altitude to set up for a landing. Turns towards a dead engine are generally not advised, but in this case, the model appeared above it's Vmc and a turn towards and over the pits area was not an option.

3) The model was approximately 100 yards out, 150 feet up and in a slow, steep and decelerating climb at 1/3 throttle. When I opened the throttles to 100%, the left engine blew out it's glow plug (did not know this at the time). First indications of a problem was slight nose up pitch coupled with a pronounced yaw to the left. This quickly developed into a left-handed spin with a nose down attitude of approximately 45 degrees (distance, wind, and other models in the air mean only feedback was visual - no relyable sound to go by). The throttles were immediately brought back to idle and the control surfaces released to neutral. -no change, model completes 2nd revolution. Down elevator was applied, no change, model completes 3rd revolution. Opposite rudder was added, model exits spin after completion of 4th revolution. Completed recovery from dive with less than 15 feet to spare (I think). Airspeed looked good, so the throttle was opened enough to stretch the glide to the runway.

4) similar to 2)

Cheers,
-E

Walter D

My Feedback: (16)

I'm going to copy this answer which I wrote a few days ago when talking about a DC 3:

I've flown quite a few twins (never a DC 3 though), and on every one of them, I've found out that it was much easier to turn toward the dead engine, and my thinking tells me why this is:

1) When one engine quits, the airplane will automatically start a gradual turn toward the dead engine.

2) As the airplane is already on a bank, lowering the other engine to about half throttle the turn is very easy to maintain.

3) Opposite rudder input to the dead engine, should keep the airplane flying straight and level, a slight pressure on ailerons can make a difference on some models also.

4) If trying to turn toward the good engine, more rudder and aileron deflection is necessary, thus contributing to a faster loss of airspeed, which could result in a stall and spin, and the DC3 is very good at doing that.

5) By all means, once you have the airplane trimmed out and are sure of its gliding capabilities (and if you are gutsy like me), put less fuel on one engine first, go up, and see how it behaves when the engine quits, of course, be way up there; try this with both engines, learning this will eventually save your airplane some time, it has served me well.

6) When one engine quits, lower the other one to half, and do not try to gain altitude abruptly, you will be asking for disaster, specially if you have a tail wind.

7) Always start your take off run so as to have as much runway ahead of you as possible, if engine quits, immediately lower the other one and land, in many instances is a better idea not to lower the gear at such a moment.

8) Have flaps, a little tad of flap deployment can help you get a longer glide, when both engines are shut down, or one is at least at idle or slightly above. For sure no more than 10 % deployment.

9) The .46's will easily overpower this airplane, even .40's can be a little too much, the best combinations I've seen fly (I'm talking about the Royal kit) was with .35's.

KingwoodBarney's tale about having his Beech Kingair for such a long time and with so many flights must be a record, to have that many flight on a twin and on a Kingair makes it material for the Guiness Book of World Records, wow!
Warbirdz1 is very right when he says that a wide open area flying field can be extremelly helpgul when flying a twin and an engine quits at the worst time, which can be anyone that is too close to the ground!

I had many engine out situations and most were induced by me, just so I could learn how to handle things at the right moment, it is best to try this after 3 or 4 flights and you have learned how well the airplane glides with engines at idle or just above, and how it behaves with flaps, from these observations is why I say that turning toward the dead engine could be on your favor and not against you.

Here's a true story of what happened to me when flying my Royal Cessna 310, this airplane was powered by to .45 2 stroke engines, it weighed 12.5 lbs. Great flying twin, but fast and very pitch sensitive when flaps were deployed.

On a very early Sunday morning, flying out of a cow pasture which had trees just about everywhere by the side of the runway, toward the east end there was a fairly wide circle that had trees all around, this circle was more to the left of the runway, so if at that point you had not gained about 100 feet, you've had it, turning to the right was not an option as there were trees but toward the left there was some chance of survival, because of that big circle which was clear in the center, but the perimeter was surrounded by very big Ficus trees.

The 310's throttle are gradually advanced (no flaps were used), very solid take off run, at about 3/4 of the length of the runway it takes off, gear goes up, altitude about 50 feet, left engine quits abruptly, by now I'm right at the end of the runway, I still had to gain another 50 just to clear the top of the trees at the far end of the runway, as soon as the engine quit, the airplane started to drop the left wing (not violently though) as I automatically dropped the other engine to half when noticing the bank I had no better choice than to continue on that self imposed turn and kind of tightening it a little by adding some up elevetar, wings were at about a 30 deg. bank, I held it there by the use of ailerons and a tad of right rudder, I started flying around the circle at about half tree level, but only a small portion of the circle was under my view, as trees started blocking me, all I could do was pray and keep the input on the controls always keeping a slight pressure on the elevator (which by now had become like a rudder, tightening the circle. Very early in the morning that .45 sounded so lonely out there, no other sound around, but I was expecting to hear that dreaded noice of broken balsa and tree limbs, for what seemed an eternity that is all that was going on in my head, when suddenly there appears the 310 at exactly the same bank attitude and same altitud coming around the big circle, I immedietaly lowered the good engine to idle, banked hard to the right lining her up with the runway, gear down, flare and touchdown, whewww!, was that a save or what!, I was patting myself on my back, as unfortunately I was the only one at the club at the time (told you it was early), when all my buddies started arriving I told them the tale and I don't know if they all really believed me, probably the same will happen here, but it was the true, I'm telling you!

twinman

My Feedback: (2)

OK I'm in and I think this is a good idea to share experience.
I have several "Bashed Twin Trainers" that are over powered for aerobatic work.

DO NOT DO WHAT I AM DESCRIBING!!!!

My favorite take off with these planes is gaining as much speed on the ground as possible. (After the manditory vertical test at full throttle for 10 seconds) Max airspeed is to give me control in the event of engine failure. Always take off aimed away from the flight line to do this. Never take off parallel to the flight line.
I take off straight up, rolling straight up, and into inverted flight and roll out level at altitude.
Sounds neat, looks great, but...very dangerous for long plane life.
Here is what happens if ( And when) one engine dies going straight up.
As other posts talk about, the inverted snap roll is often the result of engine loss. High power and slow speeds make this worse. ( Slow speeds can also, in the above manuver, mean hanging on the props)
The snap roll will happen..NOW! What is different, is that the plane was flying straight up at good speed due to take off run. When the flat spin hits, the wings go from vertical to flat or horizontal to start the spin. Here is the exciting part....all that speed you gained on take off is instantly stopped with the wings now parallel to the ground and you have no airspeed and no altitude. Needless to say, this take off should be done away from the flight area.
To get out of this mess, means instantly go to idle, aim the plane straight down, by inputting up elevator, to gain air speed, advance the throttle to one half ( Or what your plane can take) and pull out . Yaw is not really a problem going straight down. Plan to shake for sometime the first time this happens, but plan for it if you do aerobatic type take off's with a twin.

flying2bill

My Feedback: (2)

My first twin was a Royal P38 swap meet special, you know the one, a little crooked, overweight, powered by Supertiger .40's. The plane had been around 15-20 years, been through 1/2 dozen owners, a few different engines, and never been flown. After the first flight adjustments (1/8 up aileron on right wing, level on the left) I got about 10-12 flights out of it before the one engine tumble of death. I was just flying laps (left hand pattern) when suddenly in the middle of a left turn the 38 did a snap to the right. I immediatly cut the throttle and did some opposite rudder stuff, it did quit the spin after a few revolutions but now we are out of airspeed and altitude, resulting stall was disasterous, got to admit the wild tumble looked neat.

twinman

My Feedback: (2)

To flying2bill
My first P-38 was also the wing hobby shop special and the engine out spin, also killed it. That is why I have done so much experimenting with two gyros, one for rudders and the other for the ailerons.
They do dampen the yaw and spin to a point that you can react before the "Spin of Death"
Been there, done that, don't want to do again.
Good Luck

TexasAirBoss

My Feedback: (22)

What do think about this? I've read a few threads now that mentioned guys loosing control almost instantly when they lost an engine. It seems that they are usually flying either P38's or B25's. I wonder if it isn't related to the tail surfaces. Two small fins might not provide the stability of one large fin. And when you scale it down, perhaps there simply is not adequate fin area. On top of that, one fin is either blanked out by a nacelle in front of it or at least is in pretty dirty air. Now the plane is left with only one very small fin and rudder that simply isn't adequate. An inadequte fin could raise the Vmc above the plane's normal cruise speed. That would explain why an airplane would be uncontrollable before it has even had time to slow down . This design, twin fins, was abandoned a long time ago by most of the real aircraft manufacturers. Even the Short brothers went to a conventional tail in the 80's. Nobody makes planes with tails like that anymore. If the design had merit, would'nt they still use it? Ok, I'm going to duck and cover now..............

CSpierings

My Feedback: (29)

I'm flying a 103" 15 pound Vickers WEllington with two Magnum 52 four strokes. THe wing loading isn't all that bad, don't know the wing area. I've lost an engine 6 times with the plane.

First time was on take off on the first flight. I aborted teh take off and set it down with the gear up. One wasn't all the way in and the plane was mushing in. The partially retracted gear leg bent and sent the plane skidding across the ground and into a safety fence and fence post. Damage was minimal to the plane. The gear leg was spaghetti.

The second time I lost the right engine on the downwind to land. In this case, I kept the nose down, speed up and landed. Taxing was difficult.

The third time was at a field with corn field all around. TWo other bombers were already flying with bigger gas engines so I had trouble hearing my engines. The pilot boxes were also above the runway on the side of a hill. I lost the left engine because I didn't refuel. Got distracted. It was awfully sluggish on take off. I should have aborted since I was having to hold plenty of rudder, I should have known something was funny. The plane got airborne and was climbing out at a very shallow angle. I wasn't going to clear the corn so I pulled more up elevator. Keep in mind I didn't know the engine was dead. She flipped over and went straight in from about about 20 feet up. Crunched the nose back to the wing leading edge and ripped out the tailwheel.

The other times have all been mild events typically ocurring due to fuel exhaustion and often when on final or base. No damage.

Chris

twinman

My Feedback: (2)

The prototype P-38, full size, had such small rudders that it was unstable in normal flight and they were enlarged slightly for production. I have numerous twin tail bashed planes and very large rudders. They are a blast to fly and engine out is not a problem at all.
The problem to me, with the P-38 is the high wing loading, widely spaced engines, small rounded fusalage sections (No side stability for yaw), and small rudders.
I have had one engine fail in level flight at near full speed and had them flip over. My Aerotech from England came along after much experimenting with gyros, and they do help......A LOT!!!
The other problem with this, is that we are always "behind" the plane. We cannot feel the engines going out of sync or yaw beginning, so by the time it happens, it is too late.
There was special training for the P-38 full size to handle engine out, but many were killed until procedures were developed.
My two cents....use gyros.
Twinman

roadtrip

For twinman
I want to use the Fma Co-pilot in my Morris P-38. I know that one will control both pitch and yaw, but would an additional one be of any help, or not possible? Also, what do you think of the "air speed sensor for flaps" from Arcavion?

twinman

My Feedback: (2)

I have no experience with the auto pilots, so hesitate to answer.
My experience is with the use of two separate gyros, and for me, it is worth the extra work to install.
Auto flaps????? Not sure on that one. Would it also couple to the elevator to prevent ballooning up as the flaps go down?"
Good Luck,
Twinman

AmishWarlord

My Feedback: (5)

I think the G2 is the way to go to learn to handle engine out problems with twins. I've crashed 100's of 114" P-38's now and now I can fly one engine all day long. No need to land just because one engine is out. Glad I didn't have to pay for all those models


Things I have learned,

1 USE RUDDER!

2 Take off at a shallow angle going fast. If you lose an engine when you are on a 60` climb at full power and slow speed you going to spin. If you are in a low angle climb and gaining speed more than altitude and lose an engine you just keep climbing.


3 Under powered planes crash more than over powered ones. On the G2 the DC-3 is set up with OS 40 LA's. It's very hard to fly one engine. If you lose an engine your coming down simple as that. If you switch the engines to OS 52 4's the planes handles much better and can hold altitude. This goes along with twinman's advice that you should power the plane with engines that can fly the plane solo. If you bash a 40 size kit you use two 40 size engine rather than two 20's. Looks like the spinning is more from torque than from thrust so a small engine that has to be at full RPM will tend to spin more than a large engine at 1/2 power.

FLYBOY

My Feedback: (11)

kingwoodbarney, I just have to ask why you didn't get rid of that king air a long time ago. Flying the Turbo Commander for 10 years, not one engine failure, the Westwind Jet, 1 engine failure in 3 years, luckily I wasn't on it. That king air sounds like it had some problems. Scarey.

As far as the rudder size everyone else is talking about, the larger rudders do help a ton. You have to remember that the P-38 was made to be unstable and unforgiving. They had counter rotating engines, which they put the decending blade on the outside of both wings instead of the inside. This made both engines critical. It made the airplane very easy to turn tight because the arm on both engines was farther from the center of gravity. Loosing one engine at any speed was a handfull. The larger engines on the sim on the dc-3 allow you to keep more airspeed, which helps keep the plane upright. If you slow the plane down and are using one engine, the results are the same, but at a little higher speed because of the increased power.

Training on twins is a blast. I was in the back of a senica before I learned to fly and they shut one down and landed. I thought it was dumb then, but now I know it was. That plane is way under powered and would have been bad if they had to do a go around. There would have been senica parts everywhere.

AmishWarlord

My Feedback: (5)

I read that eight pilots died in one engine out training last year.

twinman

My Feedback: (2)

To AmishWarlord
I also have practiced with the G-2 P-38, but would suggest that you make sure the weight is correct. A Zeroli P-38 weighs at or around 50 pounds. Some of the flight characteristics did not feel right until I added even more than the actual weight. Right meaning what my experience with the P-38's feels like. It should fly "Heavy" and not glide well.
Good Luck

TexasAirBoss

My Feedback: (22)

No, not a real King Air, it was a model. Some days are just like that. I would have days when I just could not get things to go right and have two or three engine failures. Then I might go 6 or 7 months without one. Here is Houston, the late fall and early winter make for a mixed bag of weather, one day it might be 80 degrees and two days later it is 50 degrees. So that time of year I am constantly retuning engines. These engines were a bit tempermental . But even though it might average out to about one in sixteen flights, they generally came in clusters. I was actually pleased with the model. However, the engines were O.S. Max FP 40's with bleed air idle adjustment. As the engines got older and older, (one was two years old when I built the King Air), they lost power and blew fuel out around the front bushing. My 11 minute tanks slowly turned into 9 minute tanks. And I had to fly at pretty much full power all of the time in order to have a nice feel about the plane. When it was new, I could easily come back 5 or 6 clicks from full power. This helps greatly. Sometimes when one engine was a little sour, I could just throttle back a little and it would sweeten up. Toward the end, I really could only back off about one or two clicks of power and it was noticeable immediately. So, what to do. Buy two more lame FP's? Spend nearly 300 on a pair of BB engines for an airplane that old? Or sell. I wasn't flying that much at the time, (new girlfriend) and I was feeling my luck was just about used up anyway. I have acquired a Bridi Shrike that I will do up Bob Hoover style one day. One day when I am flying 3 or 4 days a week and feeling sharp again.

FLYBOY

My Feedback: (11)

Boy Kingwood, I missed that one. Sorry bout that. Glad it was the model and not the real one. Would have been wondering about that.

OldRookie

My Feedback: (13)

I like the idea of using gyro's in a twin to give you a little more time to react.
Could any of you that have used gyro's, explain what needs to be done to set up the plane.

Greg