ASW-15b Landing gear doors

[Dick]

A Happy New Year and Greetings from Western Canada!
The Edmonton Soaring Club operates ASW-15B C-GRXQ.  My question concerns the operation of the landing gear doors. 
I would be most grateful for any information please, a hand drawn sketch, or photo, or very detailed explanation of the where the bungees or springs attach to the gear structure (or fuselage somewhere?)
Each door has a metal loop on the inside about 10 cm from the forward point of the door.  We assume one end of the spring or bungee attaches at this position, but we are having problems identifying where the other attachment points are.
Any help much appreciated.  Thanks
Dick Parker.   

[Johan van Ravenzwaaij]

Hi Dick and welcome to the community!

very detailed explanation of the where the bungees or springs attach to the gear structure (or fuselage somewhere?)
Each door has a metal loop on the inside about 10 cm from the forward point of the door.  We assume one end of the spring or bungee attaches at this position, but we are having problems identifying where the other attachment points are.

You are right about the metal loop in the door. That loop is connected with a bungee through a waterhose of about 20 cm (to keep the doors open when it's extended). The other end of the bungee is attached to a short metal strip of about 6 cm. This strip has two holes; one for the bungee and one of the size of the diameter of the bolt used for the main wheel. The strip is slightly bent outwards and fits in the U-shaped piece of the under carriage, where the big bolt goes into the main wheel.

In this case a photo would say more than a thousand words, but I hope you can follow me.

[Dick]

Hi Johan.  Very many thanks for your quick reply.  I have identified the metal strips you mention. Each is secured under the nut and bolt head of the wheel axle, and each has an additional small hole.  Each metal strip has one leg bent outwards and both have marks on the edges  These marks match with other marks on the inside of the doors.  As the landing gear starts to lower, the tyre contacts the doors first, pushing them open half- way, and then the strips take over and push the doors further open as the gear extends fully and enters the down lock?
You mention waterhose, so I think maybe this could also be a 20 cm length of polythene tubing maybe?
What diameter of bungee do you use?
What is the static length of each bungee?
How do you attach the bungee ends?  (hooks, split rings, knots)
I should know the answers, but I have taken over a long repair project on our ASW-15 in which the landing gear and flying controls in the centre fuselage were all removed for repair access last year.  I have the glider ready now, and the doors and hinges re-fitted, but I cannot remember how the door bungees are connected!
I apologize for so many questions!
Terlet? In 1967 my club (Two Rivers Gliding Club, RAF Laarbruch, Germany) had a weekend expedition to Terlet.  We flew our tiny B-Spatz and Ka-6CR on the winch.  I remember a great launch to around 1,500 ft in the B-Spatz, and lots of really good soaring!

[Johan van Ravenzwaaij]

Hi Johan.  Very many thanks for your quick reply.  I have identified the metal strips you mention. Each is secured under the nut and bolt head of the wheel axle, and each has an additional small hole.  Each metal strip has one leg bent outwards and both have marks on the edges  These marks match with other marks on the inside of the doors.  As the landing gear starts to lower, the tyre contacts the doors first, pushing them open half- way, and then the strips take over and push the doors further open as the gear extends fully and enters the down lock?

That's right.

You mention waterhose, so I think maybe this could also be a 20 cm length of polythene tubing maybe?

Yes, but the tube needs some flexibility. Please keep in mind, I recall this from memory: it could be longer or shorter.

What diameter of bungee do you use?

About half a cm

What is the static length of each bungee?

I have no idea: I never loosened it. You should experiment with this: the doors are quite firmly closed. (And when  you hear your doors opening while side slipping; the bungees are too loose  )

How do you attach the bungee ends?  (hooks, split rings, knots)

A knot

I should know the answers, but I have taken over a long repair project on our ASW-15 in which the landing gear and flying controls in the centre fuselage were all removed for repair access last year.  I have the glider ready now, and the doors and hinges re-fitted, but I cannot remember how the door bungees are connected!
I apologize for so many questions!

No problem, glad to be of help. Some pictures of your project posted here would be appreciated.

Terlet? In 1967 my club (Two Rivers Gliding Club, RAF Laarbruch, Germany) had a weekend expedition to Terlet.  We flew our tiny B-Spatz and Ka-6CR on the winch.  I remember a great launch to around 1,500 ft in the B-Spatz, and lots of really good soaring!

You are right and always welcome!

[Dick]

Johan. Many thanks for all your valuable help.  I've got the landing gear and doors functioning perfectly now.  Hopefully I will have the annual maintenance completed soon and then we have to simply wait for early May, a snow free airfield and the first thermals of 2012.  -30C this evening in Edmonton! Have a great soaring season, and thanks again.  Richard.