Spad Glides like a brick

[Rob Russell]

I have built 3 spads Hell on rails, Derringer and a pizza box They fly ok but they glide like a brick can some one tell me why.
I have a Bulsa and foam plane call a Limbo Danser you can fly that till it runs out of fueil then do 1 or 2 circles be fore you have to land.
This plane has a very thick leading edge with a thick wing about 2in could this be why ?

[woodsy]

The Pizzza box and the J wing type SPAD's glide like a brick because they basicaly fly on the prop not on the wing, the J wing glide can be improved by moving the CG back as far as your comfortamle with, try balancing them with a full fuel tank.

the HOR should glide great, i have one set up as a slope soarer and the glide is fine, try moving the Cg or maybe the all up weight is over the top

[Rob Russell]

Hi Woodsy yes I know the Pizza box hangs of the prop.
The hor is the one that dosent glide so well,I just weigh it and it's just over 2 kil I've wheals on mine and has a OS blue 40 on it,Is that to heavy.
Did the plans come through I sent you

[woodsy]

Plans came through no probs thanks.
My Hor weighs 1.5kg with an OS20 and glides fine, i'd say the wing loading is probably to hiegh for a real good slow glide, try going to a wing thats about 48"x12" including ailerons (someting like DPS wing size).
I've also found that V tails seem to run out of elevator real quick when the speed bleads off.

[Rob Russell]

How do you keep the weight down?I mad mine out of 2mm but I put a bit of down pipe on the u chanel to hold the tank and the battery and reciever.
My wing is 48"x12"Including ailerons with about 3" of dihedral.
The spar in the wing is only 15mm.

[Rob Russell]

How do you keep the weight down?I mad mine out of 2mm but I put a bit of down pipe on the u chanel to hold the tank and the battery and reciever.
My wing is 48"x12"Including ailerons with about 3" of dihedral.
The spar in the wing is only 15mm.
I've got a OS blue 40 in mine.
Have you got wheels on yours?

[woodsy]

Ok'y Dok'y

with the Bigger wing, 40la and LG and U chanell fuzz that could easily add the extra .5kg.

the problem may be the aspect ratio with the 15mm spar, the smallest spar i have on any of my 12" cord wings is 25mm.

a smaller aspect ratio (thin wing) is better for high speed but the slow speed glide suffers a thicker wing should help.

also a flat bottom wing is better for a glide, also make sure the spar is at about 25 - 28% of cord and balance is 25 - 30% of cord

[Rob Russell]

Yeah woodsy Like I said in the first thread I thought that the wing was to thin because my Limbo Dancer has a thick wing and that thing glides for a long way.
I mite make a knew wing and see how that goes
The LA 40 will handle the weight ok.

[rlt55]

I've got a couple of SPA3Ds that seemed to fall out of the sky during dead-sticks, but after I learned to put the nose down and get up some speed, they glide home just fine (just a bit fast).
I only crash them when the engine dies close to the ground now.

[Rob Russell]

Hi rlt Yeah I have Senior Moments it must be age.
Yes I find the same problem with my spads.
I have a plane (Limbo Dancer) made of balsa and foam wing and I fly that till it runs out of gas and it will for along way.
I'm going to make a knew wing and I'm going to make the spar 50mm to see if that will help
If you want a great plane to fly get a Limbo Dancer,they dont look flash but that is a nice plane to fly.
It will fly slow and still loop in its own lengh,The name of the plane is what it will do.