Kitfox Yacht Tender/Built in Lifting Rings/ Best Model

[badmash]

For a while I have been playing with adding a small float-plane to act as the tender to my 20m Classic Motor Yacht, currently based in Florida, which I've just finished restoring. (The benefits of stopping flying winged death for the govnmt to found my own company)....

My intent would be to use the deck crane to lift the Kitfox onto and off the boat, so my first question is:

Does the forum hive mind think it would be possible to weld lifting rings onto the aircraft frame (covered with zips/press stud flaps of aircraft covering material) to attach a lifting harness directly to the aircraft when it needs lifting, or will this bend the airframe? I'm thinking 3 rings ahead of the c of g and 2 rings aft, attached to keep the aircraft in balance when it's lifted.

Further, I guess you could weld a plate between a number of stringers and attach the lifting ring to the plate to spread the load?

The alternate is to use a sling under the fuselage, which would take an awful lot longer and be a lot more hazardous.

2) Whilst due to the size of the aircraft there will be float limitations, are any particular Kitfox models known as better Floatplanes/Amphibs than others? As this is an experiment my preference would be to buy an older and cheaper model to test the concept, then look at building an aircraft once I know whether it will work or not and what tweaks for the application need to be made. Ideally I'd like to keep empty weight below 400KG, though am happy with keeping it on the experimental register, as opposed to the LSA register.

Thanks in advance for any help.
Badmash

[badmash]

Having just looked at a picture, perhaps what would actually be best, might be to use the 4 points where the float connects to the fuselage as the lifting points, using padded straps to avoid damaging the fuselage fabric, KISS.

http://www.teamkitfox.com/Forums/att...0&d=1251942389

[Av8r3400]

IMO, easiest would be the 4 spar pins where the wings attach to the fuselage.

Replace pins with bolts and include a tab with an eye to attach to lift rigging.

[Dave S]

Badmash,

I second Av8r3400's opinion.......your CG will be within the rectangle described by the 4 attach points and it is a very sturdy location - plus no slipping of a sling to damage the sides. A person would have to modify the corners of the windscreen...but that should not be a big deal.

FWIW - the ends of the upper carry through tubes (which is adjacent to spar pin/bolt points discussed) are where the BRS folks design the attach points for the straps for their whole plane parachute for the Kitfox - which would certainly expose those points to far greater stresses than your lifting rig ever would if the parachute were deployed.

Sincerely,

Dave S
KF 7 Trigear
912ULS WArp Drive

[Esser]

I vote where the spar pins are as well.

[herman pahls]

Since I often fly into road less strips, I thought it would be a great idea to already have the bolts with eyelets that Larry suggested installed in especially the rear spar and a pre-made sling so in the event a helicopter is the only way out it would do very little or no further damage.
I have seen full size float planes in the Puget Sound, Washington lifted on and off yachts in this same manner.
I have a 950 pound gross model 2 Kitfox for sale that would be close to your weight range.
Herman