ASW-15 Weight & Balance

[Robert Francis]

Hi I have been looking to purchase a 15, have found a few but the weight and balance indicates a low useful payload ~180lbs, empty weights in the range of ~500-510lbs.  Is this common ?  This is quite a discrepancy from the factor specs!  Also can I use the 900lb gross that is listed against the ASW15B for the ASW15.  Does anybody have an explanation for this, I'm 185 but throw a parachute and some coldweather gear on and I'm out!  

Post edited by: birddog, at: 2004/05/27 08:27

[John Rider]

I have a 1970 ASW-15, My empty weight is 476 pounds. The gross weight for this model is 700. Over time glider add weight for repairs oxygen systems ect. At this weight I have a usefull load of 224 pounds.

JR

[Joshy]

The older 15s ( until No. 256 ) have Balsa wood inlays.
Empty mass 220-230 kg.
Newer than 256 have conticell layers in the wings.
Empty weight around 250kg.
Max TOW is 408 kg.
Max mass except wings is 220 kg.
So you have to look what fuselage and elevator has as mass.
This you reduce from 220.
e.g. My own has 105 kg fuselage and 9 kg elvator.
Means 114.
220-114 is 106 kg.
And this is the max. usable load.

Water ballast is only allowed up to 408 kg mass.
That means: if you have a mass of 106kg ( incl. parachute ),
the wole glider 255kg, you are at a DOW of 361kg.
Water ballast max 47kg than you are at 408.

If you have 80 kg ( incl. parachute ) like me
you are allowed to take 73 kg of water.

BR,

Joshy

[Johan van Ravenzwaaij]

Mine has also a max usuable load of around 105 Kg. (That's about 231 Lbs)

@ Birddog: does the plane involved has had a (paint) overhaul? If so, what would the weight be before the overhaul?

[Robert Francis]

Yes there is new paint, also spar repair.  It is also a ASW15 not a B model.  If I understand correctly the B model has a higher usefule load.  I am currently proceding with purchase of B model in Florida, can you tell me how to get TN documents ?

[Joshy]

TN see other thread.

If there is repair and new paint look in the files.
The weight and balance reports in history have to be there.

The A model is up to No. 183.
The B model is from No. 184.
Up to No. 256 all ( incl. B ) have Balso in the wing layer.
From No. 257 there is conticell in the wings.

The A model has a MTOW of 318 and no water allowed.
The B model has a MTOW of 408 incl. 90 kg water.

For your question:
The allowed load is not depending an A or B model.
Only on mass of the fuselage and elevator.

And not all B models are equipt with water system.
In my own I had to rearm this.
Its a little bit work.

BR,

Joshy
See above.

[Johan van Ravenzwaaij]

birddog wrote:

Yes there is new paint, also spar repair.  

Looks like your lady gained some weight along the way.  :laugh:

In this case take a very good look at the (repair) journals!

[Robert Francis]

this was very useful, thanks alot.

[Robert Francis]

I don't see how what you say is true, considering the ASW15 and ASW15B's empty weight is approx. same 485-505 lbs, yet MTOW is 200lbs higher in B model.  Yes this is for water ballast but it also allows for a higher cockpit load or higher "Permitted Weight at non-lift-developing members".  See previous replies.

[Joshy]

I see you don´t understand...
Please ask Mr. Waibel.

http://www.alexander-schleicher.de/galerie/typen_galerie/galerie_einsitzer51.htm

The useable load ( in the fuselage... ) has nothing to do with the allowed water ballast.
The water ballast depends on the MTOW.
The usable load in the fuselage depends on torsion moments for the wings.
And this is to calculate max Permitted Weight at non-lift-developing members minus actual Weight at non-lift-developing members.
This is the usable load.
And it is not depending on type of ASW15.
If you do not overload this the torsion moment is O.K.
Because of the torsion moment the ASW15BR and BM hat to be cut by 60cm.

BR,

Joshy

[Gerry Whitson]

Birddog, I own an early ASW-15 (serial #15031).  Glider BOW=516 pounds.  Useful load=184 pounds.  Optional equip includes:  Cambridge M-Nav/Vario, Terra 720 transceiver and speaker, EW Flight Records, Garmin 92 GPS and of course the 12 volt gel cell to run them all.  It adds up, but she is a great ride.

I'm 172 pounds......and watch what I eat.     gerry

[clinton]

So what is the major problem of being over weight in a 15, Im nearing the maximum placarded limits for my 15, better cut down on beer and donuts.
No trouble trimming or flaring the glider, better to be nose heavy than tail heavy I would think (no flat spins when nose heavy).
What will happen if I do have to much beer and donuts.

 

[Gerry Whitson]

Not to be a stick in the mud......but it's illegal to fly an aircraft that's out of w/b!  You may not be able to recover from a stall or flair when landing.  You can over stress the aircraft when beyond the limits of the w/b,  If there is an accident, your insurance company won't pay....for some reason, insurance companies look for reasons not to pay up.   :huh:

Eat healthy...........I dropped 45 lbs to own my ASW-15.  This gives me 12 lbs to spare.  And she is worth it.  gerry

[Mark D. Black]

For comparison, my ASW15B S#15282 N#827 weight and balance computed 3/28/1996 has total empty weight at 559 lbs with maximum pilot weight at 254 lbs. This is great for me since i'm 220 + chute (15).
I still have room for barography, gps, camera with room to spare.

[Gerry Whitson]

I think the question is:

Can you modify an early model ASW15 and get the max
take-off weight up to 900lbs like the ASW15B,
instead of the current 700lbs. If so, what would
need to be done.