1) If you don't hit the tailwheel, you could have landed slower. Whether
or not you chose to do so is up to you. All this talk of dissipating
energy? Just put less into the equation by touching down at a slower
speed. Carrying power into the landing does result in a smoother
landing, but adds far more energy.
2) The energy absorbed by ripping the tailwheel off when it does happen
is almost entirely an axial load parallel to the boom tube. In other
words, ripping off the tailwheel slows you down by absorbing energy that
would otherwise be absorbed by the brakes, whose job is to...you got
it...dissipate energy. If the tailwheel were missing completely and
replaced with a cast-iron skid, you wouldn't damage the boom at all with
such a load.
3) Now imagine you've put in enough energy to the tailwheel
*perpendicular* to the boom so that you rip off the tailwheel. Holy cow,
that's a lot of energy! Thats a 10x295lb = 2950lb of force! I can't even
imagine what it would take to do that - a hammerhead stall 30' up
followed by a tail-first landing with zero forward speed? Seriously, how
could you do it?
So anyway, I think ripping off the tailwheel on grass absorbs energy,
but not any energy that would damage the airplane.
Has anyone ever ripped off/broken an *undamaged* tailwheel with a
landing on pavement?
ls78705 wrote:
>
>
> --- In Titanaircraft@yahoogroups.com
> <mailto:Titanaircraft%40yahoogroups.com>, "lwoods102" <lwoods102@...>
> wrote:
> >
> > Hi Hugh:
> >
> > I should have provided more information.... the picture of the tail
> wheel installation is in the photo album entitled "Larry Woods -
> modest Titan mods".
> >
> > An added comment... Yes, one can ensure that the tail wheel does not
> contact the runway by carrying a bit of power, but there are obvious
> negatives to so doing. Added runway is required for one thing, and the
> touch down speed is likely to be higher than optimum. No aircraft is
> perfect and I really love the Titan Tornado but a slightly greater
> intersect angle between the boom tube and the fuselage chromoly steel
> frame might haver banished the tail wheel contact.
> >
> > Like some others, I think the tail wheel is there for more than just
> dragging the Tornado around on the ground. The pictured tail wheel
> mount has a few interesting features. The machined base provides much
> greater contact area with the boom, thus spreading the load. It is
> also wider, to allow a wider tail wheel to be employed. The new tail
> wheel has a wider profile and proper bearings, which ensures that it
> spins up quickly, which reduces the shear forces when ground contact
> occurs. There have been no problems with it since it was installed.
> >
> > Best,
> > Larry
> >
>
> I'd kind of have to agree with Guy on this, that the tailwheel is
> intentionally weak to act as a shock absorber in the event of a harsh
> hit.
>
> This installation looks vastly stronger. I mean it's beautiful work
> looks like to me, ;), but then again this is a significant
> strengthening of the wheel assy itself but without redesigning the
> rest of the tail.... In the event of an incident, the energy is going
> to be transferred somewhere else rather than absorbed by the tailwheel
> like the original design intends.
>
> Don't know about anyone else but I'd sure like to not ever have to get
> into any kind of repair or replacement of that boom tube..... That
> thing is strong and it's _on_ there, glued and rivetted and bolted and
> etc......
>
> I'd much rather have the tailwheel rip off instead and leave that tube
> intact....
>
> As for carrying power into the flare, I sort of think of it as a
> compromise. When it's calm I'll usually do the whole flare/touchdown
> at engine-ldle, but when it's windy I'd rather have the extra energy
> input to slow the maneuver down a bit. The titan is still a
> low-inertia design (and really behaves that way with flaps deployed)
> so you need really impeccable timing in the flare to oil it onto the
> ground. Especially when it's windy you just don't have that loads and
> loads of hang time in the flare that you do with a high-inertia design.
>
> So I think it's better to accept a little more runway use and
> touchdown speed to be able to have a gentler touchdown. I think it's
> harder on the airframe to plonk it down rather than carry a little
> extra speed.
>
> JMO,
>
> LS
> >
> >
> > --- In Titanaircraft@yahoogroups.com
> <mailto:Titanaircraft%40yahoogroups.com>, Hugh Sontag <flying.hugh@>
> wrote:
> > >
> > > Larry,
> > >
> > > If you attached pictures, they won't come through on the Yahoo list.
> > > You could post them to the web site. If you do, please let us know, I
> > > for one would like to see them.
> > >
> > > Hugh Sontag
> > >
> > > >Hi Greg:
> > > >
> > > >Re tail wheel mount.
> > > >
> > > >See pics of the tail wheel mount I machined. The weight difference
> > > >is negligible and it has been bulletproof. I machined it from a
> > > >chunk of scrap aluminum. The wheel was acquired from a local supply
> > > >house and was very inexpensive. It has proper bearings and is wider
> > > >than the standard tail wheel so it spins up quickly.
> > > >
> > > >There are times when prudence requires a slow speed approach (short
> > > >field), which means that the tail wheel will contact the ground.
> > > >
> > > >Best,
> > > >Larry
> > > >Best
> > > >Larry
> > > >
> > > >--- In
> > >
> ><mailto:Titanaircraft%40yahoogroups.com>Titanaircraft@yahoogroups.com
> <mailto:Titanaircraft%40yahoogroups.com>,
> > > >"gregburcham18" <gregburcham18@> wrote:
> > > >>
> > > >> Could someone please give me an alternative to the tail wheel? My
> > > >>tail wheel is secured via 12 aluminum rivets per side which pops
> > > >>right off anytime it is even slightly bumped (sometimes I don't
> > > >>even know it is gone until I get out of the aircraft). I hate this
> > > >>thing!
> > > >>
> > > >> Any suggestions (mechanical, not flying skills) would be greatly
> > > >>appreciated.
> > > >>
> > > >> Thanks,
> > > >>
> > > >> Greg
> > > >>
> > > >
> > > >
> > > >
> > >
> >
>
>
[Non-text portions of this message have been removed]
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