accident reports and seatpan's

[HansLab]

Now that my painting project is coming to an end, 'the thing in my work-space' more and more begins to look like a real plane. Together with that I come to think several issues over, of which I wasn't very aware, before.
Accident reports is one of 'm: I googled on KitFox IV - and had a very nasty night.
Effective for ones awareness, though: I have my seats covered (very nicely!!) and had the idea of attaching them with tie-raps. Reading that one bloke got seriously injured whe the whole seatpan shuffled forward after stall-exercises (and struck 'the possibilty to steer the aileron' - how would that feel...) I am re-considering this matter... And I haven't quit reading, yet.

How did you guys get along with attaching your seat's?

Greets,

[Dorsal]

There are some good threads on this if you search "seat pan cracks" or "butt blocks".

[cap01]

Yes , it is a real concern . Dorsal is correct , there has been some good discussion on the subject . The seat storage boxes will keep the pan off the controls as will the butt blocks . I've also used adel clamp around the cross frame tubes to secure the seat pan . Before the project was completed , I was taxiing for runup and did have the front of the pan slip off the tube and it definitely does jam up the controls .

[rogerh12]

My seat pan is held in place with about 20 zip strips.
It's cheap, easy to remove and reinstall (just get more zip strips) and I am probably using twice as many as I really need (they are tough little suckers). But, I will be adding the underseat blocks too (just in case).

Roger

[cubtractor]

Definitely added the butt blocks during my rebuild after reading the threads on the subject.

[HighWing]

Hans,
Are you sure the kitfox that crashed because of a seat pan collapse was a Model IV? Could you give a link to the report?
Lowell

[napierm]

Another thing to watch on the IV is the aileron belcrank right at the left front. It crosses over the floor board edge. If the screw that holds the floorboard down comes loose it will stop the belcrank 1/2 way. There is an NTSB accident report that sure sounds exactly like this.

[rogerh12]

Because wood warps, I replaced my model 4 floor boards with good old fashion aluminum to avoid a warping interfering with the belcrank. I also added more floor board hold down screws.
(see attached);
Roger

[SkySteve]

Wow Roger. That really looks nice!

[GWright6970]

Roger, what sheet thickness did you use? It sure looks great!!

[SSFoxBuilder]

May be overkill, but with this being such a popular topic we figured a little carbon fiber reinforcement wouldn't hurt.

[rogerh12]

Steve;
Glad you like them.
These floor boards have been redesigned to be sectionalized and interlocking to reduce flex to almost zero and also allow removal and access to the control bearing backing nuts, so that I can disassemble and grease the controls even with the fabric installed.
They weigh in at about 3 ¾ lbs, the green and red blocks are magnesium spacers . The plates are just 5052 aluminum, 0.050 inches thick. I just used the stock wood boards as patterns, so the came together pretty fast.
Hope this helps
Roger

[HansLab]

Thanks for all your comment, gentlemen, it really helps! However, I did not ment the seatpan to break down (onto the tubes), but the seatpan to come loose! And shuffle forward - right into the stick...
Got the (old) news while surfing - wille try to get the url back for you.