On Feb 14, 7:23 pm, "J.Kahn" wrote:
anon wrote:
A couple of folks have built their Himaxes and Minimaxes as trikes. On the
surface, it doesn't seem like an overwhelmingly difficult engineering
problem to overcome. How deluded might I be?

Moderately to extremely depending on how design/engineering savvy you
are. If someone has a successful installation just copy that.

Be careful designing landing gear mount structure. Taxiing over rough
ground is really hard on gear, harder than bumpy landings. I've seen
some gear on ultralights that looks scary. Watched one collapse on
landing several years ago. And have heard of other gear failures on
homebuilts. We had a gear failure on a Glastar about five years ago,
when the single AN5 bolt sheared during braking after touchdown. The
gear is a round, tapered steel rod mounted in a steel tube socket
welded to the fuselage cage structure, and that AN5 bolt passed
through the tube and leg. Braking forces try to turn the rod in the
socket and landing/turning/taxiing loads try to push it inward, and
that bolt couldn't take it. After the repairs, it had a single 3/8"
NAS bolt, about three times stronger than the original AN5. Didn't
break no more.
So it ain't as simple as it looks. Worse, nosegears have to
be strong enough to take a lot more abuse than a tailwheel. The whole
weight of the airplane comes against the nosegear in a botched landing
or on touchdown on a really soft surface.

Dan

Dan