Ed's T-Raider
04-03-2005, 01:18 PM
#1
Ed's T-Raider
The weather cooperated and I got to test the T-Raider (Twin Sky Raider Mach II). The bottom line is "Yippeeeee!!" This is one great flynig plane-for my style, anyway.
Basic idea was to build a P-82, Twin Mustang, style, twin fuselage plane from 2 World Models Sky Raider Mach II ARF kits. At my local hobby shop, these kits go for $53 & change so the total kit price was less than a good single engine kit.
Here's the T-Raider ready to go.
Basic idea was to build a P-82, Twin Mustang, style, twin fuselage plane from 2 World Models Sky Raider Mach II ARF kits. At my local hobby shop, these kits go for $53 & change so the total kit price was less than a good single engine kit.
Here's the T-Raider ready to go.
04-03-2005, 01:28 PM
#2
RE: Ed's T-Raider
T-Raider wing: We extended the wing by 14 inches center-to-center.
The tip rib was traced and 3/32 knocked off all around and made new ribs. The full length dihedral brace is 1/4 ply (in our case, we laminated two 1/8 ply pieces). The new dihedral brace is 22 inches long-14 inches plus 4 inches that it is inset into each side. Stock dihedral was used and it worked out well in flight.
In the center of the center section, you can see the 1/4 square doubler for the hatch. The center rib will be cut away for the receiver and battery.
My buddy and builder, "Flaps" Laffert holds the wing before center sheeting was applied.
The tip rib was traced and 3/32 knocked off all around and made new ribs. The full length dihedral brace is 1/4 ply (in our case, we laminated two 1/8 ply pieces). The new dihedral brace is 22 inches long-14 inches plus 4 inches that it is inset into each side. Stock dihedral was used and it worked out well in flight.
In the center of the center section, you can see the 1/4 square doubler for the hatch. The center rib will be cut away for the receiver and battery.
My buddy and builder, "Flaps" Laffert holds the wing before center sheeting was applied.
04-03-2005, 01:52 PM
#3
RE: Ed's T-Raider
Rather than build a 1-piece stab, we decided to do two separate fuselages and join the stabs when the fuselages were mounted on the wing. The stabs were shortened to 13 inches each. This gave us a 7-inch section on each side on the inside and 6 inches outboard of the fuselage. I calculated this length to give me a good stab area of 23-25% of the wing area.
Flaps decided the center stab section had to have a straight leading edge so he built a new leading edge.
We thought of all sorts of stab joining methods, but ended up doing it the easy way. Flaps inset a length of hardwood and we used a brass strip and a landing gear strap to hold the stab tips together.
The Sky Raiders come pre-hinged. When we cut the stab and elevator off, there was a long section without a hinge so I used a technique from my old control line days-a figure-8 hinge using Kevlar line.
Flaps decided the center stab section had to have a straight leading edge so he built a new leading edge.
We thought of all sorts of stab joining methods, but ended up doing it the easy way. Flaps inset a length of hardwood and we used a brass strip and a landing gear strap to hold the stab tips together.
The Sky Raiders come pre-hinged. When we cut the stab and elevator off, there was a long section without a hinge so I used a technique from my old control line days-a figure-8 hinge using Kevlar line.
04-03-2005, 02:05 PM
#4
RE: Ed's T-Raider
The radio compartment and hatch are in the new center section. The switch is mounted off to one side.
8 servos were used, 2 each for elevator (JR 811 digitals), aileron (2 old JR 4001 coreless), rudder (2 Hitech 5625 digitals) and throttle (2 something or other, GWS standards, I think). I used a JR 770 7-channel, PCM receiver and a 6 volt battery pack. Also needed are lots of Y's and extensions. The throttles are on 2 different channels and mixed. The ailerons are set for flaperons on 2 channels.
Since my test using out thrust, I used Ernst thrust plates to put in 4-5 degrees of out thrust. The Sky Raider has about 2 degrees of right thrust built in so it took an extra 2 degree plate on the left side to neutralize the right thrust. Then more plates were added for the out thrust.
8 servos were used, 2 each for elevator (JR 811 digitals), aileron (2 old JR 4001 coreless), rudder (2 Hitech 5625 digitals) and throttle (2 something or other, GWS standards, I think). I used a JR 770 7-channel, PCM receiver and a 6 volt battery pack. Also needed are lots of Y's and extensions. The throttles are on 2 different channels and mixed. The ailerons are set for flaperons on 2 channels.
Since my test using out thrust, I used Ernst thrust plates to put in 4-5 degrees of out thrust. The Sky Raider has about 2 degrees of right thrust built in so it took an extra 2 degree plate on the left side to neutralize the right thrust. Then more plates were added for the out thrust.
04-03-2005, 02:09 PM
#5
RE: Ed's T-Raider
We had gear bending on the Outsider and had to replace the 5/32 wire gear with 3/16 so we started with a new 3/16 wire gear for the T-Raider. These were fitted to the stock gear mount holes which were reamed out for the larger size wire.
04-03-2005, 02:11 PM
#6
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RE: Ed's T-Raider
TRAGEDY AT SANTA ROSA !
Ed neglected to tell you about the horrible event that happened on the first take off. Not quite to flying speed, the left engine just shut down. No warning. We all yelled, seeing the plane start wild gyrations heading for the grass, then for all the parked cars, then toward where we were standing... but wait - it didn't veer the least bit, didn't circle, almost made no differenced at all. It just kept going straight and took off.
Flying with one GMS 47 engine the plane climbed out with no trouble. Ed kept it going, was doing turns into the dead engine. he rolled it a few times, and did a couple loops. He said later it took about four clicks of rudder trim to make it fly like an ordinary sport single.
Next flight both engines ran well. At the end of the flight, well, I'm sure you've heard of an "Excrement Ingesting Rictus," that's the kind of grin Ed had on his face. Said it was one of the nicest flying planes he'd ever flown.
Congratulations, Ed, looks like you and Flaps have another winner.
Bill.
Ed neglected to tell you about the horrible event that happened on the first take off. Not quite to flying speed, the left engine just shut down. No warning. We all yelled, seeing the plane start wild gyrations heading for the grass, then for all the parked cars, then toward where we were standing... but wait - it didn't veer the least bit, didn't circle, almost made no differenced at all. It just kept going straight and took off.
Flying with one GMS 47 engine the plane climbed out with no trouble. Ed kept it going, was doing turns into the dead engine. he rolled it a few times, and did a couple loops. He said later it took about four clicks of rudder trim to make it fly like an ordinary sport single.
Next flight both engines ran well. At the end of the flight, well, I'm sure you've heard of an "Excrement Ingesting Rictus," that's the kind of grin Ed had on his face. Said it was one of the nicest flying planes he'd ever flown.
Congratulations, Ed, looks like you and Flaps have another winner.
Bill.
04-03-2005, 02:33 PM
#7
RE: Ed's T-Raider
I made 3 flights on the T-Raider.
Flight 1: This was a trim and take it easy flight. The tail came up quickly and the plane tracked down the runway straight. After a few clicks of trim, it needed up and left, I made some turns and a low fly-by. After about 5 minutes, I came in for a landing. The plane floats a slight amount and is pretty easy to land.
Flight 2: Just before lift off, the left engine quits. Bill Robison, who was out for the test is hollering, "You've lost an engine!" I kept on going. I am sort of spring loaded that way-balls to the way. There was a little yaw on lift off, but not much. Once airborne, it felt like a lower power sport plane. I gave it a few clicks of rudder trim-I didn't have nearly as much out thrust as is in the Outsider so all the yaw wasn't cancelled.
I am flying around the field making left turns and Bill remarks, "You're turning into the dead engine." True, but remember, this isn't a heavy scale plane, it's an overpowered sport plane and it has out thrust. I can effectively do anything I want with one engine out without worrying much about it. If you haven't tried out thrust and experienced an engine out with it, you can't realize how nice it is to not worry about it.
I am still going good onemy right engine so I start doing rolls and a loop or 2 just to see how the plane reacts. It doesn't track as well through loops, but it flies like a slow sport plane.
Flight 3: Now I have it all together. Both engines hauling. I take off and rotate vertical and keep going. I love it. I throttle back and drop back down to where I can see the plane and try some rolls. Rolls are slow-I knew I should have cut the ailerons off and installed wider ones. Loops are good, both insides and outsides. I do an inside-outside 8 and the plane does it well.
Next I try some knife edge. Remember, I have Hitech 5625 digitals on rudder with a 6 volt pack. I have some rudder grunt if I need it. Hey, I don't need full rudder or even half. The thing climbs in knife edge. I try it both directions and it's the same. The next time by, I hold full rudder and it climbs over the top! A knife edge Immelmann. That's impressive. I love it.
Time to bring it down. Darn those 8 ounce tanks.
Flight 1: This was a trim and take it easy flight. The tail came up quickly and the plane tracked down the runway straight. After a few clicks of trim, it needed up and left, I made some turns and a low fly-by. After about 5 minutes, I came in for a landing. The plane floats a slight amount and is pretty easy to land.
Flight 2: Just before lift off, the left engine quits. Bill Robison, who was out for the test is hollering, "You've lost an engine!" I kept on going. I am sort of spring loaded that way-balls to the way. There was a little yaw on lift off, but not much. Once airborne, it felt like a lower power sport plane. I gave it a few clicks of rudder trim-I didn't have nearly as much out thrust as is in the Outsider so all the yaw wasn't cancelled.
I am flying around the field making left turns and Bill remarks, "You're turning into the dead engine." True, but remember, this isn't a heavy scale plane, it's an overpowered sport plane and it has out thrust. I can effectively do anything I want with one engine out without worrying much about it. If you haven't tried out thrust and experienced an engine out with it, you can't realize how nice it is to not worry about it.
I am still going good onemy right engine so I start doing rolls and a loop or 2 just to see how the plane reacts. It doesn't track as well through loops, but it flies like a slow sport plane.
Flight 3: Now I have it all together. Both engines hauling. I take off and rotate vertical and keep going. I love it. I throttle back and drop back down to where I can see the plane and try some rolls. Rolls are slow-I knew I should have cut the ailerons off and installed wider ones. Loops are good, both insides and outsides. I do an inside-outside 8 and the plane does it well.
Next I try some knife edge. Remember, I have Hitech 5625 digitals on rudder with a 6 volt pack. I have some rudder grunt if I need it. Hey, I don't need full rudder or even half. The thing climbs in knife edge. I try it both directions and it's the same. The next time by, I hold full rudder and it climbs over the top! A knife edge Immelmann. That's impressive. I love it.
Time to bring it down. Darn those 8 ounce tanks.
04-03-2005, 02:37 PM
#8
RE: Ed's T-Raider
Bottom line of the T-Raider: One of the best twins I have flown. This isn't very many, less than a dozen, but it is one fun airplane.
It was easy to build if you have built planes before. Sure it isn't as easy as a complete ARF, but you are only extending the wing of an ARF and chopping off the stab.
Flaps is sketching up what we did. They aren't full size plans of the center section, but I don't think these are needed. As soon as he gets them done, I'll scan them in and have them available for anyone who wants them.
I will try to keep it in 1 piece for the Chattanooga twin meet in June and our meet in Pensacola in September. See you there.
It was easy to build if you have built planes before. Sure it isn't as easy as a complete ARF, but you are only extending the wing of an ARF and chopping off the stab.
Flaps is sketching up what we did. They aren't full size plans of the center section, but I don't think these are needed. As soon as he gets them done, I'll scan them in and have them available for anyone who wants them.
I will try to keep it in 1 piece for the Chattanooga twin meet in June and our meet in Pensacola in September. See you there.
