Taping Schempp-Hirth glider wings

Anyone got any clever ideas for preventing the edges of the tape lifting as it goes round the curve at the rear of the wings - especially on the lower surface?

I have had 4 SH gliders and not really cracked this issue. It is dificult to get thin enough foam strip. The best idea I have come across so far is to use a short section of broad tape laid in a straight line over the curve but even that doesn't always stick properly on the lower surface where the curve merges into the wing fuselage angle. I also always try to let any stretch out of the tape before laying it down in positon.

I am sure other SH owners will know what I mean so what's the best technique? I am fed up with the buzzing noise.

Buy an AS glider instead!

At 12:30 06 May 2002, Howard Franks wrote: Howard,

Hmmm. I am just running the implications of this suggestion through my mind.

I could say to my wife 'Darling, remember that glider we bought 6 months ago - yes that's right the one for which you have to work full time to send the kids through university so I can afford a decent set of wings - well the sticky tape isn't working properly so I'm going to get another one.'

Or, I could try another less life threatening option.

I'll sleep on it.

Hi John,

If it's the slightly concave section near the trailing edge you're talking about, then yes.

Don't pull the tape tight as you place this bit on the wing. By avoiding tension in the tape, there should be no lifting tendency.

I have a section like this on my glider. The highly cleaned and polished (WxBlock) area takes 3M wing tape fine without lifting if you're careful to avoid that tension.

Tension is fine along the convex sections, but not here.

Is there really such a thing?

Around here everyone seems to use regular electrical insulation tape, available for 50c a roll in any gas station. Works fine, sticks to the concave bit on the underside of the PW-5 wing, comes off easily when you want it to.

Hi Bruce, There are 'wing tapes' sold by several glider repair/sales organisations. Much more expensive than electrical tape. The only problem we have found with electrical tape is that it is not wide enough for some of our old wood/fabric gliders which have large gaps to be sealed. Works well for glass ships though. Cheers, John G.

> 3M wing tape Is there really such a thing? Around here everyone seems to use regular electrical insulation tape, available for 50c a roll in any gas station. Works fine, sticks to the concave bit on the underside of the PW-5 wing, comes off easily when you want it to. |

I knew someone would ask that.

What I meant was the same kind of electrical tape that's great for wings but made by 3M. Luckily, one of the hardware stores around me stocks it as their 'premium' electrical tape. Not much more than the cream/puss colo(u)red 50c tape.

That 50c tape is fine, great, no problems at all..... until I bought a new glider. Then I realized two things simultaneously:-

That 50c tape made my old glider look good. IE whiter I wasn't going to put it on a clean new shiny glider.

What I didn't mean was the really wide and non-elastic 3M tapes that are/can be (your choice!) used for control gap sealing/mylar/whatever. Yes, they are good for gliders with more challenging wide gap-sealing applications but don't have the endearing look of duct tape.

If your gap tape is coming loose on the trailing edge, check the following :- Is there fore and aft movment in the wing fittings ? it does not need much play to make the tapes come loose especially underneath at the trailing edge, remedy fit shims to the drag pin fittings. Is there up and down movment at the trailing edge, same as above, but shows the rear drag pins are worn, check the pins for wear next derig, Schemp Hirth seems to have this problem on all there gliders from Cirrus thru to Discus, and unless you are specifically looking for the problem it is easily overlooked.

Chris Runeckles Western Australia

Ex Std Cirrus and present Discus owner

3-M white electrical tape works fine on the Discus wing. can't get it for 50 cents a roll, but it is probably thinner than the gas station tape you are buying. I'm going to check this out.

I went thru this problem right after I bought my Discus B. I got one of two sounds: Either the high ear-piercing shreek, or the 'Harley' low pitched buzz. Either is enough to illicit a full spoiler deployment on a 10kt day just get some peace and quiet!

I bought a couple of rolls of the 'Super tape' for $10 per roll only to find out it was worse than anything I had tried. It came off twice on tow!

My buddy (30 year experienced soaring pilot) suggested 3M No 35 white electrical tape. About $3/roll at Home Depot. It leaves little, if any residue and sticks the best I have found, even over freshly WX Block/Sealed surface.

The other trick is to not put ANY tension on the tape when laying it down. Stick the end of the tape to the trailing edge, pull out about 8' and then let it relax completely before laying down on wing and pressing down well. Try not to rub length-way along the tape as this will tend to put tension on it, but rather press it down Then pull out another 8' or so and repeat. (don't cut off 8 ' strips!, just pull about that much off at a time so you dont have too much to work with.) You can 'cheat' your way around the curve with slight tension on the outside edge of tape and none on inside. Takes a little practice, but does work.

Get rid of the tension and the expensive tape and your problem should go away.

Good luck, and keep the Discus!

Deputy Dog (K9) Discus B

A related Discus (A) question comes to mind.... On many occasions, I have had water ballast infiltrate the cockpit while on final glide. My initial theory was that the ballast dump valves were leaking into the cockpit when actuated. Further tests ruled this out.

I now believe that the problem is caused by de-bonded wing root tape. If the tape is not well-adhered on the, underside, cusp portion of the wing, large quantities of water are 'blown' into the fuselage during the dump. I'd estimate that over 1 gallon of water can get into the fuse during a single ballast dump.

Has anyone else had this problem??