aerotow hook position beneath a glider

[robk]

I have just bought and set up a second hand CMPro Discus 2650mm span which is meant as a slope soarer as there is no tow hook. However, we are beginning to start aerotowing at our field and I was wondering where I should put the hook to take advantage of this option. I have seen the commercially available nose fitted releases but my battery fills up this space to get the CG right. Could I instead fix a simple hook without servo release in front of the CG on the underside? Or perhaps I need to do the same but with a servo release to make release more certain? I would strengthen the fuselage first of course. Thanks in advance for any help.

[Mike Bell]

My (very limited) experience with aerotow tells me that whatever else you do, a positive servo operated release mechanism is vital. If things get a bit exciting on the climb out, and at some stage this will happen, you need to be sure you can disconnect the glider instantaneously.

As for the attachment position I would avoid placing it too far back otherwise the glider will assume an excessively nose high attitude. You could counter this by passing the tow line through a guide fixed to the nose of the glider but have the actual attachment/release point further back.

[Philip Ogden]

If I remember right from the old Keil Kraft free-flight gliders, 30' forward of the centre of gravity was a good starting point.

[David perry 1]

Well of course its only modelling and its your model so its all up to you but received wisdom (learnt the ard way) says that you really must have a means of releasing at the glider end just in case / when it all goes wrong.

The nose release is the best method by far but a hook under the nose will work - at least i have had it work for me.

Towing is great fun - we (my boys and I) were doing it only friday...almost cut the wing off the glider with the line bt my boys wont be told how to do these things by a crusty old dad. Quite right too.

Whatever you do, enjoy it.

D

[jrman]

+1 for 30Deg forward of the CG

[Speedster]

Tjek this:

https://www.youtube.com/playlist?list=PLWto3tazMLB_PZOS0b5Zw7UR8mKJ_aU-4

 

Cheers Soren

 

Edited By Speedster on 17/07/2016 20:45:39

[Frank Skilbeck]

Posted by jrman on 17/07/2016 20:20:20:

+1 for 30Deg forward of the CG

That's great for a winch or bungee launch where the glider is "kited" up, but not for aerotowing, but as Soren notes it doesn't need to be in the nose just as close to it as practical for aerotowing, a reliable release is required if you don't want to be in the tug pilots bad books

My larger (circa 4m) scale gliders have the release in the nose but the Parkzone K8 I have has the aerotow release on the bottom just behind the nose and that tows up fine, the separate bungee launch hook is 30 deg forward of the C of G.

[Darrell Woodward]

I've never done aero-tow but have done flat field, where one sets the hook 28 degrees forward of CG +/- 2 degrees...... if you think of the whole bungee, winch launch and running tow-ee 'flightpath' this makes sense, but to tow from that far back (I think) would put the glider too far above the tow plane for safety

From what I've seen / read here: **LINK** an Aero-tow release does not Have to be located the pointiest point.... at a guess some of the models have the aero-tow hitch at 80 degrees in front of CG.

[Former Member]

[This posting has been removed]