Hi there;
I am just finishing up a 1/4 scale SE5a built from Dennis bryant plans. I am a little concerned about the weight as all set to go it is 21 lbs 4 oz. (this gives a wing loading of 22 oz./sq.ft). The engine is the Moki 50cc 4-stroke gas engine (once distributed by RC showcase). It's power is of the order of a g-38 or a 1.80 4-stroke. Does anyone have an opinion as to how this palne will fly. I would certainly welcome any experiences or input. My guess is the power and weight are ok for scale flight and prototypical aerobatics, but that this plane will not be a true floater as my lighter sopwith pup.

Thanks
Redbaron

A full scale SE5a at 1410 lbs dry and a wing area of 444 sq ft had a wing loading of about 51 oz/sq ft if my calculations are correct.
http://en.wikipedia.org/wiki/Royal_A..._Factory_S.E.5

IMHO - Your 1/4 scale at 22 oz/sq ft flying a 50cc, G-38 or Saito 180 should be flyable with power to spare. At 1/2 throttle (once airborne) I'll bet you model will fly very scale like.


I'm curious to get your actual flight characteristics now.

The 50cc engine since it is a gasoline 4-stroke is in the power reange of the g-38 give or take. I believe your numbers are correct and if I calculate the power to weight ratio of my model and the full size they are within a few percent. Thanks for the input and I will be test flying it within the next few weeks, I'll definatly keep you informed, it's always nice to have information to compare to!

FYI I have a Duncan Hutson SE5a thats a little smaller than your and weights 17.5 lbs and flies with an OS 120 FS.

Redbaron:
I have a 1/4 scale SE5a built from a Fun Aero kit, weighing in at 23.5# with a lot of extra drag added by a full aray of 3/64" rigging wires and it flys very scale with a Zen G38 and a 20x8 scimitar prop.
Bob

Bob;
Out of curiosity at what RPM does your zenoah turn the 20 X 8 prop?

I would imagine you have plenty of power, I flew the DB 1/4 scale with a Zenoah 22cc which had adequate power. I'm planning on building another and fitting a Honda GX31cc fourstroke petrol.