Here's a question for all you master builders.
I have a SIG Extra300XS with a G-26 on it. The engine puts out 17.2 lbs of thrust but the plane weighs 15.2 lbs.

The Manufacturer say it should come out about 13 lbs.
How do I get it back down to the weight that Sig says it is supposed to come out?

I didn't do anything that I can think of that would cause it to weigh so much. Wassamatta? I did add a bit of reinforcement to the firewall but not 4 lbs. More like 4 ozs. The G-26 doesn't weigh 4 lbs more than a 2c 120 size engine. This has got me stumped. The plane flies like a rocket but vertical is BLAHHHHH!

Any ideas on how to reduce wing loading would be really appreciated.

JimRoss

Well the G 26 might not be 4lbs heavier but it got to be 3lbs heavier plus you must of had to add weight to the tail to get the CG correct plus the 26( though better than the 23) is still under powered for its weight. If you want to use gas its going to be a heavy plane.

If you want that plane at 13 lbs, put a ST2300 in it.
You will have no problems with performance.

JimRoss,
Your 300XS weighs 15.2 lbs. Sig says it should come in at 13 lbs. Isn't this a difference of only 2.2 lbs. and not 4? You can easily lose most of that extra weight with a Moki 1.35 or a Saito 1.80.

JIMROSS
THIS IS MY SOLUTION GET A RCS-140 16-8 8900 RPM MUCH MUCH LIGHTER THAN A G 26 AND MUCH MUCH MORE POWERFUL CHECK IT OUT. SEE M.A.N ISSUE MAY 2002
EMAIL YOUR HOME ADDRESS AND ILL MAIL IT TO YOU. CALL RCSHOWCASE THEY WILL TELL YOU. PJAMESRC

JIMROSS
PS RCS-1.40 IS GASOLINE $ 1.50 /GAL FLY ALL DAY AND NO CLEAN UP OR NO FLAMEOUTS PJAMESRC

PJAMESRC,
An RCS 1.40 is still 45 ounces. IMO a bit too much weight and not really enough power for the 300XS.
This plane needs a good strong glow engine to keep the weight down.

How about an OS 160 FX? I have one of those available right now.
Only flown it twice in H9 Edge 540 and never really got to wring it out. Still breaking in.

The o.s. 1.60 would be a great engine for this plane. my brother has this set up and it flys great. I had a 1.6 in a hangar 9 cap and it was phenomenal. I agree with all of the above a good strong glow or a light strong gas(I.E. zdz 40) is the way to go. good luck.

The OS 1.60FX should do nicely. A ZDZ40 is over 3 lbs. with ignition, a bit much for the 300XS.