When I got my new glider, I had the ends of the basetube reinforced
with inner sleeves, in order to better support the wheels being mounted
inboard; as I recall, there was some discussion at the time of making
sure that the inner-sleeves were properly beveled, so that they
wouldn't grind away at the inside of the basetube, leading to an
eventual in-flight failure of the basetube. (Apparently, the basetube
flexes a bit even under normal flying conditions.)
~Ralph
Re[2]: In-flight structural failure?
Moderator: CHGPA BOD
-
Richard Hays
- Posts: 315
- Joined: Wed Feb 09, 2005 9:13 am
- Location: Baltimore, Maryland
Re[2]: In-flight structural failure?
Wrong! That incident you speak of was totally different and I was around
when it happened. Jerry Lanham SPLICED a Electra Flyer basetube so that he
could more easily mount wheels on it ( long story ). However...he CUT the
basetube in half, then slid the wheels on, then hammered in a shortie inner
sleeve in the CENTER of the basetube without stress relieving the ends. He
then joined the two halves together and then bolted them to keep them in
place.
The then weaker, thinner basetubes with rounded ends flexed quite a bit
under load. They all do for that matter. But this quirky center sleeve
worked away at the inside of the outer tube and caused it to fail. Dave
Stevens died impacting the mountain halfway between launch and the rock
pile.
Ironically...he had been warned of this questionable arrangement just prior
to launching. He said he'd replace it next time.
Jerry Lanham tried to hide his manufacturing error but in a most un-ethical
manner continued to manufacture basetubes this way. I took it upon myself to
personally go after each and every one and after Jerry for that matter. I
patrolled sites looking for these basetubes and warned their owners of the
potential catastrophy. That was in 1977.
Richard Hays
>From: Vant-Hull - Brian <brianvh@umd5.umd.edu>
>Reply-To: hg_forum@chgpa.org
>To: hg_forum@chgpa.org
>Subject: Re[2]: In-flight structural failure?
>Date: Wed, 29 Jun 2005 12:39:26 -0400
>
>This may be in response to a death at High Rock many years ago. Emma Jane
>can still draw diagrams of the exact way things went together and what
>happened. It's a good example of what may seem like a good idea could
>have deadly consequences.
>
>Brian Vant-Hull
>301-646-1149
>
>On Wed, 29 Jun 2005, Ralph Sickinger (R2) wrote:
>
> >
> > When I got my new glider, I had the ends of the basetube reinforced
> > with inner sleeves, in order to better support the wheels being mounted
> > inboard; as I recall, there was some discussion at the time of making
> > sure that the inner-sleeves were properly beveled, so that they
> > wouldn't grind away at the inside of the basetube, leading to an
> > eventual in-flight failure of the basetube. (Apparently, the basetube
> > flexes a bit even under normal flying conditions.)
> >
> > ~Ralph
> >
> >
> >
> >
> >
>
>
when it happened. Jerry Lanham SPLICED a Electra Flyer basetube so that he
could more easily mount wheels on it ( long story ). However...he CUT the
basetube in half, then slid the wheels on, then hammered in a shortie inner
sleeve in the CENTER of the basetube without stress relieving the ends. He
then joined the two halves together and then bolted them to keep them in
place.
The then weaker, thinner basetubes with rounded ends flexed quite a bit
under load. They all do for that matter. But this quirky center sleeve
worked away at the inside of the outer tube and caused it to fail. Dave
Stevens died impacting the mountain halfway between launch and the rock
pile.
Ironically...he had been warned of this questionable arrangement just prior
to launching. He said he'd replace it next time.
Jerry Lanham tried to hide his manufacturing error but in a most un-ethical
manner continued to manufacture basetubes this way. I took it upon myself to
personally go after each and every one and after Jerry for that matter. I
patrolled sites looking for these basetubes and warned their owners of the
potential catastrophy. That was in 1977.
Richard Hays
>From: Vant-Hull - Brian <brianvh@umd5.umd.edu>
>Reply-To: hg_forum@chgpa.org
>To: hg_forum@chgpa.org
>Subject: Re[2]: In-flight structural failure?
>Date: Wed, 29 Jun 2005 12:39:26 -0400
>
>This may be in response to a death at High Rock many years ago. Emma Jane
>can still draw diagrams of the exact way things went together and what
>happened. It's a good example of what may seem like a good idea could
>have deadly consequences.
>
>Brian Vant-Hull
>301-646-1149
>
>On Wed, 29 Jun 2005, Ralph Sickinger (R2) wrote:
>
> >
> > When I got my new glider, I had the ends of the basetube reinforced
> > with inner sleeves, in order to better support the wheels being mounted
> > inboard; as I recall, there was some discussion at the time of making
> > sure that the inner-sleeves were properly beveled, so that they
> > wouldn't grind away at the inside of the basetube, leading to an
> > eventual in-flight failure of the basetube. (Apparently, the basetube
> > flexes a bit even under normal flying conditions.)
> >
> > ~Ralph
> >
> >
> >
> >
> >
>
>