Introduction: Hello everyone.

CB wrote:
Piano hinges with cable instead of wire hold the pod to the rest of the
airframe. Size it to resist the canopy lift load. When you pull the
plug, a spring-loaded reel yanks the cable out. The chute deploys, and
the airplane falls away from you.

Best let go of the stick, since the controls are attached to the
airframe. All that's in the pod are the seats (strap in tight!). The
control panel needs to stay with the airframe, too - waaay too many
quick-disconnects to think about there. One set for the headsets is
doable, but throttle, instruments... of course, with FADEC and a full
glass cockpit all you have is a big honkin multipin plug. No. You
still have the steam gauges as backups, so you still have the
pitot/static connection to deal with.

But now you don't have any structure under you to cushion the impact.
In fact, your feet are hanging out in space a la Fred Flintstone.
Deploy an airbag once forward speed drops?


I like it!!! In fact, the B1B pod has an airbag to cushion the landing
IIRC.

Seriously, the thing I don't like about the Cirrus system is that the
landing under chute destoys the airframe. I guess that you can
salvage the engine and the avionics, and probably control surfaces,
etc, but the rest of the airframe is toast due to the 20MPH+ touchdown.

The thing that I do like about the Cirrus is that the occupants are
likely to survive with minimal injury, and the touchdown is unlikely
to seriously damage property, or kill anyone on the ground. The problem
with an ejection pod ala F111 or B1B, or with ejection seats ala many
other military airplanes is that they preserve the occupants, but
leave the people on the ground to fend for themselves. Most of the
time that is okay...

If I was going to go to all the time and trouble to build an airframe,
and design a ballistic chute system for it, I'd like to design it such
that the airframe would survive the touchdown as well as the occupants.

(Honey, I've got good news and bad news... The good news is I'm fine,
the bad news is that the airplane I just spent the last five years
building is toast. AGGGGHHH BANG.)

The problem as I see it is how to slow the 2000LB airframe from the 15-
20MPH of the chute to stopped without breaking it. With the Velocity,
I was thinking along the lines of a nose down attitude, and something
like a BIG automotive type airbag designed such that it does a
controlled collapse on impact. That is why the pusher design was both
an asset as well as a problem. Its also why shedding 1/4 of the weight
seemed like a good idea. The occupants are better off being restrained
by their belts and harnesses than landing on the mains anyway. And it
wouldn't be so bad rebuilding a sacrificial nose cone compared to having
to start from scratch.

Now, back to reality...

Don W.

"Don W" wrote in message
. com...



I like it!!! In fact, the B1B pod has an airbag to cushion the landing
IIRC.

Once I was a lower level Federal Gov't. bureaucrat at one of our air
material
depots.The time was late 50s, early 60s. At that time flight tests were in
process for
the B-58 Hustler. Much shredded aluminum was distributed over portions of
soutwestern Oklahoma during that time. A crew escape pod was planned for
that aircraft but the early operational aircraft didn't have them. It was
rumored
at the time that many young officers were resigning their commissions rather
than accept assignment to the B-58 units. Whether true or not I never knew,
the aircraft I was personally involved with was the B-47.

Harold
KD5SAK

"Don W" wrote in message
. com...
Its also why shedding 1/4 of the weight
seemed like a good idea.


First you say you are worried about folks on the ground then you say you
want to drop an engine on them.


Now, back to reality...

Don W.



Good idea.

The B-58 was not the only airplane that had a reputation as a
"widow maker". The early jets were all notorious for unexplained
loud explosions when not under hostile or friendly fire.

You may have met a gentleman I had the pleasure of knowing briefly,
and working for. His name was Lionel Alford, and at the time I
met him he was the number two man in the Boeing company in charge
of all Boeing Military companys. Mr. Alford had been a B-17 pilot
in Europe during WWII, and was hired by Boeing shortly after the
war to be the chief test pilot on the B-36(?). He then became the
project manager for the B-52 and worked his way up the company
hierarchy from there. I had the pleasure of flying with him a
number of times. He was an amazing fellow. He died in 2000.

Don W.

kd5sak wrote:
"Don W" wrote in message
. com...



I like it!!! In fact, the B1B pod has an airbag to cushion the landing
IIRC.


Once I was a lower level Federal Gov't. bureaucrat at one of our air
material
depots.The time was late 50s, early 60s. At that time flight tests were in
process for
the B-58 Hustler. Much shredded aluminum was distributed over portions of
soutwestern Oklahoma during that time. A crew escape pod was planned for
that aircraft but the early operational aircraft didn't have them. It was
rumored
at the time that many young officers were resigning their commissions rather
than accept assignment to the B-58 units. Whether true or not I never knew,
the aircraft I was personally involved with was the B-47.

Harold
KD5SAK

If you read it carefully, you will find that I suggested allocating
a seperate chute for the 500 LB engine. Did you miss that?

Don W.

Gig 601XL Builder wrote:

"Don W" wrote in message
. com...

Its also why shedding 1/4 of the weight
seemed like a good idea.



First you say you are worried about folks on the ground then you say you
want to drop an engine on them.



Now, back to reality...

Don W.




Good idea.

"Don W" wrote

Seriously, the thing I don't like about the Cirrus system is that the
landing under chute destoys the airframe.

That has been batted around before. It is not true, in most cases. All but
a few are flying again, IIRC.

The strap that attaches the chute to the airframe is under a layer of
gelcoat, and that is ripped off, so the strap needs to be replaced, and
gelled over, but aside from that, if the aircraft does not hit any uneven,
damaging objects, there will be little extra work to do.

The problem as I see it is how to slow the 2000LB airframe from the 15-
20MPH of the chute to stopped without breaking it.

That is done by a sliding ring around the risers. When the chute first
pops, the ring holds the chute almost closed, but as the speed slow, the
outward pressure on the ring lessens, and the ring begins sliding down to
the attachment ends of the risers, allowing the chut to deploy to full
diameter.

I'm not sure if I got all of the technical names right, as I don't see any
reason to leave a perfectly good airplane, or even one that is in fair
condition! g
--
Jim in NC

Hi Jim,

Morgans wrote:
"Don W" wrote


Seriously, the thing I don't like about the Cirrus system is that the
landing under chute destoys the airframe.


That has been batted around before. It is not true, in most cases. All but
a few are flying again, IIRC.

This is news to me, however I can't refute it. I'll check with Cirrus
and get back to you. My understanding was that the impact usually drove
the landing gear up into the wings, and was severe enough that the FAA
would not recertify the airplane as airworthy because of the
inability to completely inspect a "plastic" aircraft for hidden damage.

Once again, I'll try to check into it and get back to you.

The strap that attaches the chute to the airframe is under a layer of
gelcoat, and that is ripped off, so the strap needs to be replaced, and
gelled over, but aside from that, if the aircraft does not hit any uneven,
damaging objects, there will be little extra work to do.


The problem as I see it is how to slow the 2000LB airframe from the 15-
20MPH of the chute to stopped without breaking it.


That is done by a sliding ring around the risers. When the chute first
pops, the ring holds the chute almost closed, but as the speed slow, the
outward pressure on the ring lessens, and the ring begins sliding down to
the attachment ends of the risers, allowing the chut to deploy to full
diameter.

Actually, what I was referring to was slowing the aircraft from the
20MPH descent under the chute to a sudden stop upon ground impact. You
are correct that the amazing folks at BRS and elsewhere have worked out
a good system for slowing a 2000+ LB airplane from 200 Kts to 20 MPH.

The problem is that the slower you want the descent to be, the bigger
the parachute has to be, until it is unmanageably large (and heavy).

I'm not sure if I got all of the technical names right, as I don't see any
reason to leave a perfectly good airplane, or even one that is in fair
condition! g

I agree in principle, as long as that sucker still responds to the
controls, and we are not somewhere over the middle range g

Don W.

Don W wrote:
Hi Jim,

Morgans wrote:

"Don W" wrote

Seriously, the thing I don't like about the Cirrus system is that the
landing under chute destoys the airframe.

That has been batted around before. It is not true, in most cases.
All but
a few are flying again, IIRC.

This is news to me, however I can't refute it. I'll check with Cirrus
and get back to you. My understanding was that the impact usually drove
the landing gear up into the wings, and was severe enough that the FAA
would not recertify the airplane as airworthy because of the
inability to completely inspect a "plastic" aircraft for hidden damage.

Once again, I'll try to check into it and get back to you.
Don W.

Okay, I called the Cirrus factory, and also did a web search. The
fellow I talked to was Walt Conley in California--a regional manager
and pilot who bought one of the first SR22's. According to Walt
the airframe is destroyed in most landings under the CAPs system. The
exception is if the airplane happens to come down in soft
treetops/brush. (CAPS is their BRS chute system)

They've had 10+ CAPs deployments with one that failed due to high speed
(estimated at 400 KTs). One landed in water, and resulted in an injury
due to the fact that the gear is designed to cushion the impact. In
the water landing, it obviously didn't do that.

In a normal CAPs landing, on hard surface or dirt, the landing gear is
driven through the wings, and designed crush zones in the airframe help
cushion the loads so that the occupants can walk away.

Don W.

Hi Bryan,

Seems like it would have to be a pretty big rocket to have much
effect on a 2000+ LB load, but I don't know much about those
things. If they're doing that they're pretty clever.

Don W.

Bryan Martin wrote:

You could do what the Russians have done with parachute cargo drops. Just
before touchdown, a rocket pack suspended in the parachute rigging fires a
short burst to slow the descent.


in article , Don W at
wrote on 2/21/06 11:56 AM:


The problem as I see it is how to slow the 2000LB airframe from the 15-
20MPH of the chute to stopped without breaking it. With the Velocity,
I was thinking along the lines of a nose down attitude, and something
like a BIG automotive type airbag designed such that it does a
controlled collapse on impact. That is why the pusher design was both
an asset as well as a problem. Its also why shedding 1/4 of the weight
seemed like a good idea. The occupants are better off being restrained
by their belts and harnesses than landing on the mains anyway. And it
wouldn't be so bad rebuilding a sacrificial nose cone compared to having
to start from scratch.

Now, back to reality...

Don W.

"Don W" wrote

Actually, what I was referring to was slowing the aircraft from the
20MPH descent under the chute to a sudden stop upon ground impact. You
are correct that the amazing folks at BRS and elsewhere have worked out
a good system for slowing a 2000+ LB airplane from 200 Kts to 20 MPH.

Have you ever looked at the drop test requirement that is required, for
certification? I would be surprised if the chute landing was any more
brutal than a parachute landing!

I don't remember how or where to find it, offhand, but perhaps someone has
it book-marked.
--
Jim in NC