Twin & Multi Engine RC Aircraft Discuss the ins & outs of building & flying multi engine rc aircraft here.

engine out on twin

Reply
Old 06-11-2012, 01:43 PM
  #1
halflight
Thread Starter
 
Join Date: Jan 2002
Location: Evansville, IN
Posts: 405
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default engine out on twin

please settle a debate..let's say the left engine dies..will the right engine which is still running pull to the right or left
halflight is offline  
Reply With Quote
Old 06-11-2012, 01:54 PM
  #2
mboland
 
mboland's Avatar
 
Join Date: Jul 2007
Location: BouldercombeQueensland, AUSTRALIA
Posts: 558
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

Just think of all that drag on the dead motor side, and all the thrust on the other side.

That's why you don't turn into the dead motor, cause that's where the plane is wanting to go anyway.

And it better if the right motor dies that the left, just to add fuel to your debate.
mboland is offline  
Reply With Quote
Old 06-11-2012, 02:52 PM
  #3
91zulu
 
Join Date: Feb 2002
Location: Orange, NJ
Posts: 1,298
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

Left..
91zulu is offline  
Reply With Quote
Old 06-11-2012, 04:25 PM
  #4
dasintex
 
dasintex's Avatar
 
Join Date: Sep 2004
Location: Displaced Canadian in Central Texas TX
Posts: 2,575
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

I agree, if the Left Engine goes out, the plane will pull to the Left; I think of it like a tracked vehicle, if the left track is neutral and the right track is pulling, the tank or bulldozer will pull to the Left; I have a twin and the Left Engine has gone out, and to keep it flying straight, you have to use right rudder, making left turns is easy, just let the rudder go to neutral and the plane will turn to the left
dasintex is offline  
Reply With Quote
Old 06-11-2012, 07:40 PM
  #5
Chuck54sd
 
Join Date: Dec 2008
Location: Pierre, SD
Posts: 31
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

Turn into the good engine..... Luke.... don't go to the dark side.

-Chuck
Chuck54sd is offline  
Reply With Quote
Old 06-11-2012, 08:45 PM
  #6
JohnBuckner
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,259
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

Left of course and the required corrective action among others is right rudder and not right aileron.

The old full scale training phrase to indentify just remember dead foot - dead engine. Of course with our Rc aircraft we don't have the that luxury.

John
JohnBuckner is online now  
Reply With Quote
Old 06-18-2012, 09:16 AM
  #7
aerowoof
 
Join Date: Jun 2006
Location: pembroke, NH
Posts: 2,891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

not only will it turn to the left the wing tip with the dead engine will drop and the wing tip with the good engine will rise.
aerowoof is offline  
Reply With Quote
Old 06-19-2012, 03:25 PM
  #8
maxpower1954
 
Join Date: Nov 2005
Location: Rock Hill, SC
Posts: 514
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

And of course, it's also a function of speed. An engine failure in normal cruise doesn't lead to an immediate yaw (at least in most of them!) As the speed decays, the turn becomes more pronounced.

Russ Farris
maxpower1954 is offline  
Reply With Quote
Old 06-23-2012, 09:05 PM
  #9
Thisstrangeengine
 
Thisstrangeengine's Avatar
 
Join Date: Jun 2009
Location: Douglassville, PA
Posts: 311
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

The plane will go left. Apply right rudder and dont kill the other engine. Those still props will add alot of drag and slow you down quickly. I know this from experience! I made that mistake with my Cessna Bobcat almost 20 years ago.
Thisstrangeengine is offline  
Reply With Quote
Old 06-23-2012, 09:24 PM
  #10
mboland
 
mboland's Avatar
 
Join Date: Jul 2007
Location: BouldercombeQueensland, AUSTRALIA
Posts: 558
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

I don't want to sound like I'm nit picking, but strictly speaking, an idling prop will produce more drag than the stationary ones.

Strange but true, I had to read the maths on it before I would believe it.

mboland is offline  
Reply With Quote
Old 06-27-2012, 01:29 PM
  #11
Rocketman_
 
Rocketman_'s Avatar
 
Join Date: Oct 2003
Location: , MA
Posts: 1,267
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin


Quote:
ORIGINAL: mboland

... strictly speaking, an idling prop will produce more drag than the stationary ones.
I can agree with that. I'd been flying a lightly loaded OS 1.60 powered 3D model for several years before the day the pressure pulse line slipped off the fuel pump and turned it into a glider. The engine went dead but the model didn't appear to be losing much altitude so I just kept flying it all over the place until it looked like it was time to make a landing approach.
Well, it wasn't time yet and the model flew right past me about waist high at a speed well above my normal landing speed when the engine is idling. Frantically I got the wheels down on the runway but it still rolled off the end of the runway and flipped in the tall grass. Yep, I can agree with that quote above.
Rocketman_ is offline  
Reply With Quote
Old 07-18-2012, 11:15 PM
  #12
dkm
 
dkm's Avatar
 
Join Date: Jun 2008
Location: Sydney, AUSTRALIA
Posts: 52
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

On a twin, if the left engine dies the centre of thurst moves towards the right engine. The centre of drag will move slightly left giving a resultant left yaw and left roll.
Unlike being in the cockpit an R/C pilot will not feel the yaw so "dead foot dead engine" does not apply. But an uncommanded roll (hopefully with engine noise loss)
will be the give away for the failure.
So as the model rolls, first react to the roll with right aileron, reconigise the engine failure (sound,performance etc,), put full right rudder (the direction of the aileron input).
Lock the right rudder input and ease off the aileron to neutral.
Balance rudder input to throttle, power on-rudder on, power off-rudder off.
Do not throttle back and keep the nose level to maintain speed. Speed is your friend, never fly a twin slow or use high nose attitudes at low speed.
dkm is offline  
Reply With Quote
Old 07-28-2012, 07:20 PM
  #13
Pilot P51
 
Join Date: Mar 2004
Location: Corpus Christi, TX
Posts: 190
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin


I am real pilot and I also have a real twin.
There are a number of things the pilot has to do when flying a scale twin verses flying a R/C plane when it comes to flying with one engine. The main thing is to get the plane on the ground in one piece.
Another helpful hint in flying an R/C twin, when you do lose the engine try to make your turns in the same direction the engine is running to get back to the runway, if possible. The plane will want to yaw or turn into the engine that has stopped working. Turning in the opposite direction you have a less chance of spinning the plane into the ground when making the turns.
I have seen this happen more than once. Were a pilot will recover from a lost engine but as soon as he starts his turn back to the runway he turns the plane and into the ground it goes.
Hope this helps.
Walts
Pilot P51 is offline  
Reply With Quote
Old 10-23-2012, 05:44 PM
  #14
valleyk
 
Join Date: Feb 2010
Location: littleton, CO
Posts: 209
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

I've seen alot of twins spin to the ground on one engine. The problem is its hard to know which engine is out or if an engine is out. Would be nice if someone could come up with a sensor on each engine that could tell the transmitter  to sound off a beep and flashing light telling the pilot what side is out. I think for very expensive twins this would be ideal.
valleyk is offline  
Reply With Quote
Old 10-23-2012, 07:00 PM
  #15
91zulu
 
Join Date: Feb 2002
Location: Orange, NJ
Posts: 1,298
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

We go by feel. The plane will yaw as soon as an engine goes out. Now how much of a yaw depends on how far apart the engines are. The further apart the more violent of a yaw you will get. That is why they saw if you going to fly twins you better be a rudder pilot, because when an engine go out and you feel a twitch your rudder finger has to be instantaneous or else you in trouble. It has to be a reflex action, not something you have to think about.
91zulu is offline  
Reply With Quote
Old 10-23-2012, 09:26 PM
  #16
Roary m
 
Join Date: Nov 2002
Location: lancaster, CA
Posts: 730
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

An engine out is something like getting a flat tire on your car while you are driving. It is a matter of compensating and taking corrective action.
Roary m is offline  
Reply With Quote
Old 10-26-2012, 09:18 PM
  #17
invertmast
 
invertmast's Avatar
 
Join Date: Dec 2003
Location: North Port, Fl
Posts: 7,645
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine out on twin

In single engine ops with a multi engine airplane, airspeed is king! Without it, its going to spin in. If your in level cruise, add the rudder input and power quickly (not instantly, quickly, its more important to be accurate and fast, that it is to be instant and wrong!). If you are in a climb, quickly add the correct rudder input, get the gear up and lower your rate of climb (remember, airspeed is KING!). If you ever find yourself in a situation where you have full rudder input and the airsplans is yawing in the opposite direction, Immediately lower the nose and reduce the power (you are at at under the minimum controllabable single engine airspeed), to increase your airspeed, slowly add power as the airspeed increases and then start a slow climb again.
invertmast is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 11:10 AM.