homebuilt safety

Thanks for taking time to deal with more detail. Although
you included many more issues than I raised. And I am sure
the KE/mv confussion was just a slip of the pen. But let
me just clarify some things:

Richard Riley wrote in message . ..
................
But there seems to be something wrong there, too. The KLS web site
doesn't seem to exist any more, but the old numbers I have in my files
show a sea level max gross climb rate of 2200 FPM. Since the Cozy,
with it's lighter max weight, only claims 1200 FPM at 2050 gross, the
Speed Queen number seems optimistic to me. The same is true on the
top end - SQ claims 258 MPH Vmax, Cozy 4 claims 220 mph and
demonstrates (CAFE test) 209.8 mph at 1668 lb, 29.2", 2691 rpm, 12.9
gph.
...........

KLS website is gone because KLS is in process of changing name. KLS
was a partnership and one of the partners left. The new name
is Advanced Composite Design, Inc. KLS has also just finished developing
a new desing of a large plane (tested and flying). Thats explained at my
website http://www.abri.com/sq2000

I just came back from SQ2000 factory training.
I haven't tried the factory model to Vne. I was mainly interested in
take off and landing skills. But Stan indicated he achieves 230mph
cruise. But isn't Cozy IV fixed main gear? That would explain some of
the difference.

Landing that fast increases risk, limits the airports you can land at,
and increases wear. .........

True. But in my case we have two 6800 x 150 foot runways. In SQ2000
factory flight training I was instructed to touchdown at 90MPH and did
consistently and the bird exhibited no problem behaviour. I am sure
that after I get a lot more hours experience like you or Stan, I'll be
able to cut the landing speed. If you are around Pierre, SD you are
welcome to check out my bird.

Interestingly, while on the subject of safety, about 6 weeks ago, the
KLS SQ2000 came down in a storm and busted the landing gear. It slid
down the runway and into a ditch. No injuries, it did not flip over,
and surprisingly the damage was mainly to the landing gear and the
prop (toothpicks all over) - very little other damage.

And, as everyone knows, nothing ever goes wrong. There is never
anything on the runway that shouldn't be there. You never have to
land on a shorter runway than you intend, and you never land at higher
than expected density altitude.

Not to mention off-runway landings... there's the real rub for safety.

If the runway is smooth but short, you may have the choice of what to run
into at a reduced speed. If it's an off-runway situation, you'll be
touching down at whatever flying speed, and encountering surface
irregularities at higher speeds.

It's easy for folks to only consider some emergencies when justifying their
risk profiles. Of course, I've never done that :-)

Ed Wischmeyer

On 19 May 2004 07:52:18 -0700, (Paul Lee)
wrote:

:KLS website is gone because KLS is in process of changing name. KLS
:was a partnership and one of the partners left. The new name
:is Advanced Composite Design, Inc. KLS has also just finished developing
:a new desing of a large plane (tested and flying). Thats explained at m y
:website http://www.abri.com/sq2000

Stan's run through another partnership? That's about on schedule,
they last 3-4 years or so in this business. So that's Shirl, Kurt and
now Keith.
:
:I just came back from SQ2000 factory training.
:I haven't tried the factory model to Vne. I was mainly interested in
:take off and landing skills. But Stan indicated he achieves 230mph
:cruise.

It wouldn be it would be Vmax, not Vne, - maximum cruising speed, not
never exceed speed. I'd be *very* surprised if Stan was getting that
- 360 Long EZ's do 230-235 mph wide open. The 360 Berkut does
235-240, and that's with half the fuselage, and a couple of hundred
pounds less than the Speed Queen. He's probably around 220, a few mph
faster than the Cozy.

:But isn't Cozy IV fixed main gear? That would explain some of
:the difference.

As I said in my previous post, it would explain *some* of the
difference, but not much. A well faired gear produces as much drag as
a couple of whip antennas of the same length.
:
: Landing that fast increases risk, limits the airports you can land at,
: and increases wear. .........
:
:True. But in my case we have two 6800 x 150 foot runways. In SQ2000
:factory flight training I was instructed to touchdown at 90MPH and did
:consistently and the bird exhibited no problem behaviour. I am sure
:that after I get a lot more hours experience like you or Stan, I'll be
:able to cut the landing speed. If you are around Pierre, SD you are
:welcome to check out my bird.

The aircraft is capable of a lower landing speed (or it isn't, but it
probably is). If it is, then you can certainly change your mind and
land slower. The thing that worries me is that you're being trained
to land that fast, and being told that it's a good idea.

:
:Interestingly, while on the subject of safety, about 6 weeks ago, the
:KLS SQ2000 came down in a storm and busted the landing gear. It slid
:down the runway and into a ditch. No injuries, it did not flip over,
:and surprisingly the damage was mainly to the landing gear and the
rop (toothpicks all over) - very little other damage.

Composite airplanes are surprisingly strong. I know of one that was
flipped over by a dust devil on final, hit inverted and tumbled. The
pilot broke his leg, the passenger got a cut on his forhead. Another
lost it's engine on final, went through trees, touched down on a
freeway going the wrong way and went head on with a car. The pilot
was completely unhurt, though every part of the airplane was broken.

Any idea why the airplane ripped out it's gear? I know it was in a
storm, but did he catch the gear on something on touchdown? Excessive
sink rate? The gear should be able to take 3-4 G's without departing
the aircraft,

On Wed, 19 May 2004 09:02:25 -0700, Ed Wischmeyer
wrote:

:It's easy for folks to only consider some emergencies when justifying their
:risk profiles. Of course, I've never done that :-)
:
:Ed Wischmeyer

And you've never seen any emergencies, have you Ed? No blown tires,
hung gear, drug wingtips, eaten valves, frozen control systems,
clogged fuel filters. Aviation is like WestWord, where nothing can
possibly go worng.

"Pete Schaefer" wrote in message news:Btqpc.53022$536.9082680@attbi_s03...
Landing speeds are a big driver for the amount of injury. I think that the
FAA has a lot of data on this. Can't think of a reference off-hand, but you
can search the NTSB site. But anyway, here's the math: KE = (1/2)mv^2. The
basic conclusion is that accidents occuring at lower landing speeds do less
damage. This was a driver for the design of the RV series aircraft. If you
want safety, get something with STOL capability, make sure there's nothing
in the cockpit that's going to smack you in the back of the head if you
screw up, then practice, practice, practice (with an instructor until you
feel confident).....then practice some more. Avoid low-level aerobatics
until you're a really ****-hot pilot.

You really need to forget about structural protection in a home-built. The
key is to prevent (by flight procedure, pilot skill and knowledge, and by
appropriate vehicle design) accidents from happening in the first place.

Is this because none of the ones available as designs currently have
any, or because you feel it's not feasible, or because....exactly why?
Race cars go faster on the ground than some homebuilts will _straight
down_ and, Dale Earnhardt aside, usually people go in the wall and
walk out (or get pulled out by the crash wagon crew).

I recall that the P-51's designer, Dutch Kindelberger, designed the
cockpit area as the toughest structure, so everything else would
crumple around the pilot and provide protection from the sudden
impact. Is this somehow no longer feasible?

Hey Jim-Ed:


"Jim-Ed Browne" wrote in message
om...
Is this because none of the ones available as designs currently have
any, or because you feel it's not feasible, or because....exactly why?

I've never looked at any airplane designs that have such features. There is
a huge price to pay in terms of weight, required power and such to provide
pilot protection. Drives up cost a ton, and makes operations more
expensive.

Keep in mind that crumple zones are only really for front impact, too.

Race cars go faster on the ground than some homebuilts will _straight
down_ and, Dale Earnhardt aside, usually people go in the wall and

They have requirements for driver protection. And they have huge budgets to
work with. I don't know about about NASCAR, but, to get the sign-off to
race, the CART guys have to slam a couple of chassis into a wall to show
that the tub holds together. Expensive, expensive, expensive.

I recall that the P-51's designer, Dutch Kindelberger, designed the
cockpit area as the toughest structure, so everything else would
crumple around the pilot and provide protection from the sudden
impact. Is this somehow no longer feasible?

Sure, it's feasible, but it's expensive. How many airframes do you want to
build for the purpose of destroying them to prove the design? Then there's
costs of test facilities. What's the cost in weight, performance, etc.? How
much is it going to cost to design, model, and test? If you see a couple of
zeros being added on to the total cost to build and get the FAA to sign it
off, then you're probably getting a realistic picture.

Even if you could afford to buy one, operation costs of a P-51 is probably
well beyond the average budget of the typical home-builder. Besides, the
P-51 was designed to go to war and get shot at, not for $100 hamburgers.

I guess the question I have is this: How much are you willing to spend to
get an airplane that protects you in case of a crash? If you've got
millions to spend, then you can probably get what you want. But on a $50k
home-built? Forget it. Maybe a certified commercial manufacturer would have
the resources to pursue safety features like this, but I would find it
surprising if people would be willing to fork out the extra bucks for it,
given that the costs would have to be recovered through the sale of a
relatively small number of airplanes.

There are probably much better approaches to achieving leaps in aviation
safety without doing anything about crashworthiness improvments. Think
about the safety improvements you'd get just by having a more reliable
powerplant and fuel delivery system. Think about potential improvements
from sophisticated engine health monitoring (condition-based
maintenance....catch and repair faults before they become
catastrophic...there are some really nice products out there right now)?
Then there are potential benefits for IFR/night flight using synthetic
vision to prevent spatial disorientation. These kinds of improvments might
cost thousands of dollars to the consumer, falling in the range of what is
affordable to the typical RV builder at least.

Anyway, just some things to think about. If you dig around for some of the
data on NASA's General Aviation Revitalization effort (no longer going on, I
think), you can find more comprehensive info on these topics.


Pete

P.S. Just to qualify my views - I'm not an airframe designer, but I do work
in aircraft development. I'm a flight controls engineer (meaning that I'm
one of the guys who's found ways to drive up the costs of an airplane
without driving the weight up) with Lockheed in Palmdale, CA. While I don't
work directly with these design/development trades, I am regularly exposed
to the issues and compromises that they bring up. So...knowledgable, but
not an expert.

Richard Riley wrote in message . ..

.................................... When I say exactly, I mean
exactly - to the fraction of an inch in planform, with the same
templates, with the same modified Eppler airfoil on the mains, and the
same Roncz 1145 MS on the canard.............

Rich,

There is a curiosity that I found about the SQ2000. When Stan
demonstrated stall, the plane did not dip and dive (bobing) like
typical canards, but simply descended at a steady rate - or climbed at
a steady rate in a power stall. The canard just shakes slightly
almost like conventional aircraft before a stall - i.e. it failed
gradually and not suddenly. The feature shure wis handy if you
inadvertendly land too slow - it would descend at steady rate and not
dive into the ground.

I haven't seen this behaviour mentioned for other canards and Stan would
not tell me how he got that. Are there other canard designs that do
that? Do you know how it works?

---------------------------------------------------
Paul Lee, SQ2000 canard: http://www.abri.com/sq2000

On 19 May 2004 12:03:24 -0700, (Jim-Ed Browne)
wrote:

I recall that the P-51's designer, Dutch Kindelberger, designed the
cockpit area as the toughest structure, so everything else would
crumple around the pilot and provide protection from the sudden
impact. Is this somehow no longer feasible?

You do? References please. I've studied that fighter for years and
this is the first I've ever heard of Kindelberger designing the
cockpit like a modern car is designed.

Thanks, Corky Scott

"Pete Schaefer" wrote in message
newsQOqc.80298$iF6.6816727@attbi_s02...
Hey Jim-Ed:


"Jim-Ed Browne" wrote in message
om...
Is this because none of the ones available as designs currently have
any, or because you feel it's not feasible, or because....exactly why?

I've never looked at any airplane designs that have such features. There
is
a huge price to pay in terms of weight, required power and such to provide
pilot protection. Drives up cost a ton, and makes operations more
expensive.

Keep in mind that crumple zones are only really for front impact, too.

Race cars go faster on the ground than some homebuilts will _straight
down_ and, Dale Earnhardt aside, usually people go in the wall and

They have requirements for driver protection. And they have huge budgets
to
work with. I don't know about about NASCAR, but, to get the sign-off to
race, the CART guys have to slam a couple of chassis into a wall to show
that the tub holds together. Expensive, expensive, expensive.

I recall that the P-51's designer, Dutch Kindelberger, designed the
cockpit area as the toughest structure, so everything else would
crumple around the pilot and provide protection from the sudden
impact. Is this somehow no longer feasible?

Sure, it's feasible, but it's expensive. How many airframes do you want to
build for the purpose of destroying them to prove the design? Then there's
costs of test facilities. What's the cost in weight, performance, etc.?
How
much is it going to cost to design, model, and test? If you see a couple
of
zeros being added on to the total cost to build and get the FAA to sign it
off, then you're probably getting a realistic picture.

Even if you could afford to buy one, operation costs of a P-51 is probably
well beyond the average budget of the typical home-builder. Besides, the
P-51 was designed to go to war and get shot at, not for $100 hamburgers.

I guess the question I have is this: How much are you willing to spend to
get an airplane that protects you in case of a crash? If you've got
millions to spend, then you can probably get what you want. But on a $50k
home-built? Forget it. Maybe a certified commercial manufacturer would
have
the resources to pursue safety features like this, but I would find it
surprising if people would be willing to fork out the extra bucks for it,
given that the costs would have to be recovered through the sale of a
relatively small number of airplanes.

There are probably much better approaches to achieving leaps in aviation
safety without doing anything about crashworthiness improvments. Think
about the safety improvements you'd get just by having a more reliable
powerplant and fuel delivery system. Think about potential improvements
from sophisticated engine health monitoring (condition-based
maintenance....catch and repair faults before they become
catastrophic...there are some really nice products out there right now)?
Then there are potential benefits for IFR/night flight using synthetic
vision to prevent spatial disorientation. These kinds of improvments
might
cost thousands of dollars to the consumer, falling in the range of what is
affordable to the typical RV builder at least.

Anyway, just some things to think about. If you dig around for some of
the
data on NASA's General Aviation Revitalization effort (no longer going on,
I
think), you can find more comprehensive info on these topics.


Pete

P.S. Just to qualify my views - I'm not an airframe designer, but I do
work
in aircraft development. I'm a flight controls engineer (meaning that I'm
one of the guys who's found ways to drive up the costs of an airplane
without driving the weight up) with Lockheed in Palmdale, CA. While I
don't
work directly with these design/development trades, I am regularly exposed
to the issues and compromises that they bring up. So...knowledgable, but
not an expert.



Yes, there are some negatives. However, re-enforced cockpits are becoming
the norm in sailplanes. Carbon-Kevlar composites provide a lot of
protection for the weight. Gliders land a lot more slowly than even RV's
but they are expected to land off airports without damage. If you
incorporate a ballistic parachute, re-enforced cockpits are required.

No amount of strengthening of the cockpit will save the pilot under all
circumstances but it might make a difference in some situations. A modest
amount seems a good idea.

Bill Daniels

On Wed, 19 May 2004 13:49:13 -0700, Paul Lee wrote:

Richard Riley wrote in message
. ..

.................................... When I say exactly, I mean
exactly - to the fraction of an inch in planform, with the same
templates, with the same modified Eppler airfoil on the mains, and the
same Roncz 1145 MS on the canard.............

Rich,

There is a curiosity that I found about the SQ2000. When Stan demonstrated
stall, the plane did not dip and dive (bobing) like typical canards, but
simply descended at a steady rate - or climbed at a steady rate in a power
stall. The canard just shakes slightly almost like conventional aircraft
before a stall - i.e. it failed gradually and not suddenly. The feature
shure wis handy if you inadvertendly land too slow - it would descend at
steady rate and not dive into the ground.

I haven't seen this behaviour mentioned for other canards and Stan would
not tell me how he got that. Are there other canard designs that do that?
Do you know how it works?

--------------------------------------------------- Paul Lee, SQ2000
canard: http://www.abri.com/sq2000


I'm not Richard Riley, but I'll pipe up anyway.

I'm betting that there wasn't enough pitch authority to get the angle of
attack high enough to stall the canard. The situation might be quite
different if the CG was further aft (i.e. pilot only, or with pax in back).

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com