cool 1 engine approach
07-22-2005, 08:28 PM
#1
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cool 1 engine approach
Check this picture, its a supersportster 40 twin, and it appears to be very easy to handle one 1 engine at 1/2 or less throttle (although, I broke it the first time it lost an engine, hehe)
07-23-2005, 12:07 PM
#5
RE: cool 1 engine approach
Looks like you handled the engine failure well. Nice save. Hate to see someone lose a twin. There aren't many of them.
I had an engine failure today myself on my Twin Stick. The left engine quit just as I broke ground on the first flight of the morning. The plane sounded different and I didn't have vertical so I figured something happened. Since I was slow when it happened, the plane did pull a little to the left. I kept the good engine at full power and never touched the rudder. I climbed on up to pattern altitude, flew down to the turn point, throttled back and landed. I richened up the engine a couple of clicks, flip started and took off and flew the rest of the flight.
You guys can worry about losing an engine, using rudder and keeping the power back to half. I'll keep my 8 degrees offset. It doesn't look pretty, but it works.
How about sending me a couple of good digital photos of your Super Sportster Twin for my column. Send to [email protected]. Thanks.
I had an engine failure today myself on my Twin Stick. The left engine quit just as I broke ground on the first flight of the morning. The plane sounded different and I didn't have vertical so I figured something happened. Since I was slow when it happened, the plane did pull a little to the left. I kept the good engine at full power and never touched the rudder. I climbed on up to pattern altitude, flew down to the turn point, throttled back and landed. I richened up the engine a couple of clicks, flip started and took off and flew the rest of the flight.
You guys can worry about losing an engine, using rudder and keeping the power back to half. I'll keep my 8 degrees offset. It doesn't look pretty, but it works.
How about sending me a couple of good digital photos of your Super Sportster Twin for my column. Send to [email protected]. Thanks.
07-26-2005, 11:25 AM
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RE: cool 1 engine approach
I suspect Ed's 8 degrees looks just fine in the air. Obviously it works just fine too. I'm planning a twin Kaos after following Ed's reports. The results speak for themselves. Keep up the good work Ed! Mark
07-26-2005, 12:53 PM
#8
RE: cool 1 engine approach
8 degrees does look like a lot, but first, it works and second, you lose very little forward thrust despite what you might think.
Do the math: Cos 8 = .99027. This means you are still getting over 99% of your forward thrust.
You don't notice it in the air. The first time you lose an engine and keep on doing acro and making turns both directions without rudder, you'll know what I mean.
I was flying my Twin-Air and doing a Cuban-8 about to roll upright on one of the down legs and an engine flamed out. As I rolled, the plane whipped off to one side. I immediately throttled to idle, leveled out and came up to half power. I put in the correct rudder and carefully landed. The Twin-Air has a big rudder, so there wasn't a problem holding it.
On the way hold with my flying buddy, Flaps Laffert, 83, also a former military pilot and long time modeler, we discussed single engine flying. I remembered reading somewhere back in the dim past, maybe 20-25 years ago that if you used 8-9 degrees out thrust, you wouldn't have any problems. We do a lot of experimenting, with himi building and me flying, so we decided to test it. We love a project.
I bought a Goldberg Tiger 2 ARF and he installed 2 nacelles for 2 OS .46AX engines I had. We put in 8 degrees out thrust. The plane came out heavy, 9.5 lbs, but flew OK. After trimming and feeling it out, we started the testing.
I fueled 1 tank full and the other one only got 11 of 33 cranks of fuel. After take off, I started doing acro without regard to the engines. It's one thing to throttle back and shut one down, but another to have it happen unexpectedly. The engine quit and the plane hardly even yawed. I flew some more and tried some acro-rolls in both directions and loops. Loops were hard due to the weight of the plane, but everything else was fine. I made a normal pattern and landed. The next flight I switched tanks to partial fill and it worked out the same.
At a later date, I changed engines to a Thunder Tiger .46Pro with a Tower tuned muffler and an 11-6 prop on one side and a plain bearing Thunder Tiger .42GP with stock muffler and a 10-6 prop on the other side. Out of sync, I would say. This combination flew fine. I could not tell I had mismatched engines.
After this testing, I am a big proponent of engine out thrust. My attitude now is not to worry about it. If one quits, so what, I have the other to get me home.
If any of you do any more testing to get concrete results, send them to me. I'll get them in print in my column. It's not how it looks, but how it flies that counts. (Engineer talking)
Do the math: Cos 8 = .99027. This means you are still getting over 99% of your forward thrust.
You don't notice it in the air. The first time you lose an engine and keep on doing acro and making turns both directions without rudder, you'll know what I mean.
I was flying my Twin-Air and doing a Cuban-8 about to roll upright on one of the down legs and an engine flamed out. As I rolled, the plane whipped off to one side. I immediately throttled to idle, leveled out and came up to half power. I put in the correct rudder and carefully landed. The Twin-Air has a big rudder, so there wasn't a problem holding it.
On the way hold with my flying buddy, Flaps Laffert, 83, also a former military pilot and long time modeler, we discussed single engine flying. I remembered reading somewhere back in the dim past, maybe 20-25 years ago that if you used 8-9 degrees out thrust, you wouldn't have any problems. We do a lot of experimenting, with himi building and me flying, so we decided to test it. We love a project.
I bought a Goldberg Tiger 2 ARF and he installed 2 nacelles for 2 OS .46AX engines I had. We put in 8 degrees out thrust. The plane came out heavy, 9.5 lbs, but flew OK. After trimming and feeling it out, we started the testing.
I fueled 1 tank full and the other one only got 11 of 33 cranks of fuel. After take off, I started doing acro without regard to the engines. It's one thing to throttle back and shut one down, but another to have it happen unexpectedly. The engine quit and the plane hardly even yawed. I flew some more and tried some acro-rolls in both directions and loops. Loops were hard due to the weight of the plane, but everything else was fine. I made a normal pattern and landed. The next flight I switched tanks to partial fill and it worked out the same.
At a later date, I changed engines to a Thunder Tiger .46Pro with a Tower tuned muffler and an 11-6 prop on one side and a plain bearing Thunder Tiger .42GP with stock muffler and a 10-6 prop on the other side. Out of sync, I would say. This combination flew fine. I could not tell I had mismatched engines.
After this testing, I am a big proponent of engine out thrust. My attitude now is not to worry about it. If one quits, so what, I have the other to get me home.
If any of you do any more testing to get concrete results, send them to me. I'll get them in print in my column. It's not how it looks, but how it flies that counts. (Engineer talking)
07-28-2005, 09:23 PM
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RE: cool 1 engine approach
Well, Ed, that´s ireffutable (did I write it ok?) logic, and obviously any way to improve the planes 1 engine performance is greatly appreciated. Anyway, my plane has wood cowls and I can´t imagine how to fit 8 degs into them. I must build somethin else without cowls and try your proposal, but I am very confident it will work great. Thanks for the imput.
PS I´m trying to get you the photos. I´ll PM you when I have them
Colmo
PS I´m trying to get you the photos. I´ll PM you when I have them
Colmo
07-29-2005, 08:54 PM
#10
RE: cool 1 engine approach
Other than two washers behind the engine mount on the inboard set of mounting screws my Duellist has no out thrust. I did move the engine nacelles in one rib bay.
Engine out performance is great as long as you have the altitude and air speed. I have done a couple go-arounds on one engine with this bird. I was landing too fast and would have overshot the runway...easy on the throttle but it worked!
Engine out performance is great as long as you have the altitude and air speed. I have done a couple go-arounds on one engine with this bird. I was landing too fast and would have overshot the runway...easy on the throttle but it worked!
08-04-2005, 04:08 PM
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RE: cool 1 engine approach
Hi Ed!
First of all I am impressed that so many people fly twins or multis, on my "airport" I am always alone with my twin...
Well, so far I have some years of experience with my first scratch built plane, a Armstrong Withworth 38 "Whitley". It is by far not scale, but it flies still very well. It has a Wingspan of 1.80 meters, a weight of 4.5 kg, for the wing profile I used the NACA 2415 whitout washout which I think is always a good joice, and it is powered by two 30 year old O.S. .40 four stroke engines and with them it is hopelessly overpowered.
When I was up to build that bird I had a look on the Junkers Ju 52. The wing engines are mounted with an outward angle of about 5 degrees, so I just copied this. On my Whitley the engines pull 4 degrees outward. The point is that the left one turns at 9000 rpm, the right one, it is in a worse condition, only at about 7500 rpm. In fligt you don't feel any tendency of the plane not to fly straight forward!
So long I have 11 flameouts in my logbook, 8 on the right side and 3 on the left side, in various different situations. Exept when it happens at take off (all you need is speed......) it is quite easy to hold it straight with the rudder and a little aileron, no matter which engine stopped, but it is very importand not to use more than about 80% of power on the running engine. So far I had no problems turning on the dead engine, but I always try not to fly a too close curve.
I would like to post some pics of the whitley as soon as i found out how i can post a pic in this forum.... ( I am here the first time so I don't know everything yet!)
Chris
First of all I am impressed that so many people fly twins or multis, on my "airport" I am always alone with my twin...
Well, so far I have some years of experience with my first scratch built plane, a Armstrong Withworth 38 "Whitley". It is by far not scale, but it flies still very well. It has a Wingspan of 1.80 meters, a weight of 4.5 kg, for the wing profile I used the NACA 2415 whitout washout which I think is always a good joice, and it is powered by two 30 year old O.S. .40 four stroke engines and with them it is hopelessly overpowered.
When I was up to build that bird I had a look on the Junkers Ju 52. The wing engines are mounted with an outward angle of about 5 degrees, so I just copied this. On my Whitley the engines pull 4 degrees outward. The point is that the left one turns at 9000 rpm, the right one, it is in a worse condition, only at about 7500 rpm. In fligt you don't feel any tendency of the plane not to fly straight forward!
So long I have 11 flameouts in my logbook, 8 on the right side and 3 on the left side, in various different situations. Exept when it happens at take off (all you need is speed......) it is quite easy to hold it straight with the rudder and a little aileron, no matter which engine stopped, but it is very importand not to use more than about 80% of power on the running engine. So far I had no problems turning on the dead engine, but I always try not to fly a too close curve.
I would like to post some pics of the whitley as soon as i found out how i can post a pic in this forum.... ( I am here the first time so I don't know everything yet!)
Chris
