Search found 145 matches

by JimCrawford
Wed Feb 07, 2024 8:41 am
Forum: PHOTOGRAPHS
Topic: Fun level going up :)
Replies: 6
Views: 9260

Re: Fun level going up :)

Smashing video.
Do you mount the camera using the wing tip fixing that holds the tie-down fitting?

Jim
by JimCrawford
Mon Dec 25, 2023 10:51 am
Forum: ENGINEERING AND MAINTENANCE
Topic: Leburg
Replies: 1
Views: 794

Re: Leburg

Hi RiP, seasons greetings. The high volts warning on the Leburg units is set to 15.5 volts so that's getting into an area where battery damage is possible, depending on the exact battery type. Some avionics may be stressed, although most modern kit is 12 & 24 volt compatible I've measured the ou...
by JimCrawford
Thu Oct 19, 2023 10:33 am
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Could be well worth looking through this very involved discussion:

https://www.homebuiltairplanes.com/foru ... ing.40086/

I find the information helpful and thought provoking.
Jim
by JimCrawford
Mon Oct 16, 2023 2:11 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Just looked it up on the web https://marskeaircraft.com/composite-design-manual $80.00, I don't recall it being that pricey, also there is the postage which was $37.00 in 2021 so you are looking at probably $130 now. However the information it contains is invaluable and very practical and I'm glad I...
by JimCrawford
Mon Oct 16, 2023 10:58 am
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Neil, Yes, flight line not attitude. I must have had a senior moment to have forgotten that. Especially as it was a particularly tricky issue competing in glider aerobatics where the flight line defines the entry speed into the next manoeuvre so has to be set up on exit from the previous right throu...
by JimCrawford
Fri Oct 13, 2023 4:31 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Hi Neil, The flaps I suggested aren't for stall modification but for pitch attitude control during aerobatics to keep the aircraft datum horizontal whether erect or inverted for aerobatic competition scoring. The Gusty and the Acro Advanced both use a beam type of undercarriage. I wonder if it would...
by JimCrawford
Fri Oct 13, 2023 1:29 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Hi Neil, Well that's a hell of a rabbit hole you've set for me to fall down! I should be doing other stuff but this is much more interesting! To summarise; you would like to investigate a carbon wing to get the benefit of reduced weight and the possibility of incorporating a section better suited to...
by JimCrawford
Thu Oct 12, 2023 10:51 am
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Paul, thanks for posting that Gusty article, very interesting. I agree that getting rid of the nosewheel is probably the single most effective weight reduction path for a Nipper. I also believe a tailwheel Nipper wouldn't be any more of a problem than a Taylor monoplane, Turbulent or Jodel, all of w...
by JimCrawford
Mon Oct 09, 2023 1:42 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: New lightweight wing.
Replies: 19
Views: 10099

Re: New lightweight wing.

Hi Neil, Is it the spar or the whole wing that you can only just lift - which would make it ~ 50lbs? I ask because I am engaged in the same exercise, although with a different aircraft, a Flitzer variant 'K' Goblin. Weight is of course the primary driver. If the spar is 50lbs (which seems a lot) the...
by JimCrawford
Sun Oct 08, 2023 3:22 pm
Forum: GENERAL CHAT
Topic: Parachute
Replies: 18
Views: 11460

Re: Parachute

Noticed an advert on gliderpilot.net for this Danish parachute manufacturer
https://www.cahoma.aero/?lang=en
they seem to do tapered packs which move either your shoulders or your bum forward to suit pilot shape and space around the seat.

Jim
by JimCrawford
Wed Sep 27, 2023 2:24 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: engine temperatures
Replies: 11
Views: 2331

Re: engine temperatures

Yes, weight is a concern. perhaps the outer tubes could be rolled light gauge aluminium, there's no necessity for them to be stainless the same thickness as the exhaust pipes. If it proves too heavy then the tubes can be stripped off and I'd end up with the RF4 style you have in the photograph. Do y...
by JimCrawford
Wed Sep 27, 2023 9:02 am
Forum: ENGINEERING AND MAINTENANCE
Topic: engine temperatures
Replies: 11
Views: 2331

Re: engine temperatures

Neil Spooner wrote:That photo doesn’t show the heat deflector in between the ex pipe and the pushrod tubes.


I guess my concentric heat exchanger tube for hot air for carb heat might perform that function.

Jim
by JimCrawford
Sun Sep 24, 2023 7:12 pm
Forum: ENGINEERING AND MAINTENANCE
Topic: engine temperatures
Replies: 11
Views: 2331

Re: engine temperatures

Thanks for that photo Neil, clearly worth a thousand words! I've got a pair of the VW Heritage pipes as a starting point but they will need to be fettled as my VW doesn't have the prop extension so the pipes would touch the prop. My proposed pipes are similar to yours but with a longer perforated se...
by JimCrawford
Wed Aug 23, 2023 12:00 pm
Forum: PHOTOGRAPHS
Topic: Fun level going up :)
Replies: 6
Views: 9260

Re: Fun level going up :)

:-D :-D :-D :-D
makes me want to abandon the domestic paperwork and go to the airfield to work on the Nipper!

There seems to be some vertical 'tramping' on the forward looking camera. Is this the mount flexing under G or prop slipstream influence?

Jolly Good Show

Jim
by JimCrawford
Mon Aug 14, 2023 9:44 am
Forum: GENERAL CHAT
Topic: Parachute
Replies: 18
Views: 11460

Re: Parachute

Hi Sven, I think I know the arrangement you describe, the pilot essentially wears just the harness and the pack is attached at the shoulders. I haven't seen one and think they are rather unusual, perhaps made to order rather than 'off the shelf', but certainly a possible solution. If your Nipper has...

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