Arebeck

My Feedback: (2)

I had a slightly damaged Super Sportster 60 hanging from the rafters in my basement along with the remnant of a Uravich OV-10 Bronco (small one) that consisted of 2 new Magnum XL28's, fuel tanks, and a flight pack. Having lost once to the twin fantasy (my fault, low, fast, through the sun inverted - ouch) I decided to put all the parts together and see if I could get it to fly.

I looked through some posts here on RCU, grabbed the plans of the Sportster and built some nacelles to fit the 28's. I should mention that I decided that I wanted to try to fiberglass the plane in anticipation of building a Pica 1/6 P40 later this winter. So I sheeted the wings, added the Nacelles, fiberglassed the wings and fuselage(3/4 oz and water based Polyurethane). Painted it up with Rustoleum and clear coated with spray on Polyurethane.

After I got it all togehter I decided to weigh the beast. In total it weighs 9 1/4 pounds. I got to thinking that the two 28's with 9x6 props might not move it very fast, so I started looking around the shop to see how many 40's I had. I was short one 40(my wife offered two 36's but I had to decline since I was on a mission!!)

I decided to try a taxi test and see if I needed to get another 40 to make it fly. Out to the field last Sunday when no one was around (some test flights need to be secret) I fired the engines up, tune them nicely and tried to taxi. I was amazed at how well the plane moved. I taxied again with the intent to get it off the ground and just put it back down. The monster lifted off and landed when I chopped the throttle.

I felt fortunate that this thing might work. It has a high wing loading, which should serve me well when I move to my P40.

Overall I am really surprised that two 28's were able to get the plane off of the ground. This got me to thnking on how would 2 28's translate into a single engine? Any thoughts out there?

This weekend I will see how well they keep it up in the air. I will post some photos after the first flight regardless of the outcome.

Fingers crossed and breath held,

Ron

BillS

My opinion only and others much smarter may not agree. Too much power is dangerous to a twin’s health. 28 “+ 28 is almost 60 and there is some added efficiency with two that I do not understand. You will gain much valuable experience by making twenty or so flights with the 28’s. Changing to bigger engines later is reasonably simple. Treating any engine out as a dead stick is a good policy. I’m flying 10 pounds plus about 30oz of fuel on two 25’s.

Bill

Arebeck

My Feedback: (2)

Bill,
The comparison to a .60 from two .28's is good to know. I flew the sportster with a .60 on before and it was OK. It was was a little lighter, about 7.5 pounds but it flew OK.

Thanks for the input,

Ron

Gringo Flyer

My Feedback: (18)

We need some pics.

Arebeck

My Feedback: (2)

I hope to get some this weekend, if and when it stops raining. In the past I refrained from photographing my planes until after the first flight. No real reason, just a habit that I got into. BUt I think that this plane was 'eyeballed' I will get some picture before and after. I hope that they look about the same.

BillS

Pictures would be good.

Bill

Arebeck

My Feedback: (2)

THe weather cooperated today so I was able to get the twin to the field. I retunedt he engines, they wer both turning ~12,700 rpm with 9x6 APC's. The engines are Magnum XL-.28. THe idle seemed reliable so I decided to see how it flys. It took off in about 100 ft. Needed some right aileron correction and it flew OK. I am amazed at how fast it does go considering the weight ~9.5 pounds. I landed without incident, keeping the airspeed up and was able to fly it a little later in the mornig. I had to wait for my knees to stop knocking. ON the second flight i did a loop and it rolled out at the top. THe next loop was a little gbigger and it went around without incident. Upon landing I noticed that one of the aileron clevis pulled out of the control rod. I don't know how long I was flying with only one aileron but that was the last flight for this day.

I took a couple of pictures.

BillS

Glad the flight went well. Sure gets the adrenaline up. Thanks for the pictures