Today's Message Index:
----------------------
1. 05:42 AM - Re: BRAKES QUESTION? (Chris Rusch)
2. 07:26 AM - Re: BRAKES QUESTION? (Bill Church)
3. 08:55 AM - Re: BRAKES QUESTION? (dgaldrich)
4. 10:07 AM - Re: Re: BRAKES QUESTION? (Greg Bacon)
5. 10:20 AM - How do we increase safety? (Robert Dewenter)
6. 10:51 AM - safety? (Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC])
7. 11:48 AM - Re: How do we increase safety? (tools)
8. 12:33 PM - Re: How do we increase safety? (Bill Church)
9. 01:20 PM - Re: How do we increase safety? (tools)
10. 01:40 PM - Re: How do we increase safety? (TOM STINEMETZE)
11. 02:17 PM - Re: How do we increase safety? (BYD)
12. 02:29 PM - Re: safety? (Dortch, Steven D MAJ MIL USA NGB)
13. 02:36 PM - Re: How do we increase safety? (TOM STINEMETZE)
14. 04:04 PM - Re: Cross wind component (TriScout)
15. 05:57 PM - Re: How do we increase safety? (Jack Phillips)
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Subject: | Re: BRAKES QUESTION? |
Thanks for all the input! I think I'm going to run with the hand brake for now....if
duriing taxi tests i dont like it, i will add something more elaborate.
--------
NX321LR
Fully Assembled
Tail assembly and ailerons covered and painted.
Wings covered and primed, one painted
Mitsubishi Powered
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Subject: | Re: BRAKES QUESTION? |
The only problem that I can see with the single lever brake is that it would likely
be very difficult to make sure that the braking action on each wheel is the
same. If you're using the brakes to hold the plane for a mag check, it will
probably be okay, but if you're trying to stop the plane from rolling into something
else, and one wheel brakes more than the other, you might end up in a
mess. Food for thought.
Bill C.
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Subject: | Re: BRAKES QUESTION? |
My Piper Cherokee has a single brake lever and it works just fine. I've gotten
to prefer it to the individual toe brakes because of the simplicity and ease
of bleeding. My philosophy has been that if I REALLY need to pivot on one wheel
because of proximity to something else, it's time for the tow bar. Never had
an issue with unwanted differential braking.
There are two caveats however. Number one is that it's on a tricycle gear airplane
and the nose wheel steering is pretty darn effective. The second is that
it's a well designed and proven system from a certified aircraft. You could
use those parts -- brake lever, master cylinder, and calipers -- and have no fear
of asymmetrical braking. Deviate from the certified stuff and you're back
to doing your own R&D but that's what experimental aviation is about.
A lot depends on other factors. If your tail wheel is the non-swiveling type or
you don't mind dragging the tail around by hand like Rob, then the single lever
would be adequate and above all else simple. If you're comfortable breaking
the tail wheel loose, then like Jack says, a dual system is necessary. My
late father-in-law had a Decathalon and he would taxi up to his hangar at a pretty
good clip and at the last minute snap the thing 180 degrees into perfect
position to pull it in. Scared the crap out of me the first time he did it but
he never hit anything. The fact that he'd been flying since WWII may have had
something to do with it. I wish he was still alive to give me a refresher
course in tail wheel.
do not archive out of habit
Dave
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Subject: | Re: BRAKES QUESTION? |
Wow, what a subjective topic. I hated the single lever on my Cherokee.
There were numerous times I wished I had differential braking for ground
maneuvering. I think the bottom line here is use what you prefer.
On Wed, Jan 23, 2013 at 10:55 AM, dgaldrich <dgaldrich@embarqmail.com>wrote:
> dgaldrich@embarqmail.com>
>
> My Piper Cherokee has a single brake lever and it works just fine. I've
> gotten to prefer it to the individual toe brakes because of the simplicity
> and ease of bleeding. My philosophy has been that if I REALLY need to pivot
> on one wheel because of proximity to something else, it's time for the tow
> bar. Never had an issue with unwanted differential braking.
>
> There are two caveats however. Number one is that it's on a tricycle gear
> airplane and the nose wheel steering is pretty darn effective. The second
> is that it's a well designed and proven system from a certified aircraft.
> You could use those parts -- brake lever, master cylinder, and calipers --
> and have no fear of asymmetrical braking. Deviate from the certified stuff
> and you're back to doing your own R&D but that's what experimental aviation
> is about.
>
> A lot depends on other factors. If your tail wheel is the non-swiveling
> type or you don't mind dragging the tail around by hand like Rob, then the
> single lever would be adequate and above all else simple. If you're
> comfortable breaking the tail wheel loose, then like Jack says, a dual
> system is necessary. My late father-in-law had a Decathalon and he would
> taxi up to his hangar at a pretty good clip and at the last minute snap the
> thing 180 degrees into perfect position to pull it in. Scared the crap out
> of me the first time he did it but he never hit anything. The fact that
> he'd been flying since WWII may have had something to do with it. I wish
> he was still alive to give me a refresher course in tail wheel.
>
> do not archive out of habit
>
> Dave
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=392952#392952
>
>
--
Greg Bacon
Prairie Home, MO
NX114D(Mountain Piet)
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Subject: | How do we increase safety? |
Fellow Piet builder/ flyers:
A long story would tell you why I signed up for a college course in
aviation accident investigations - and why at my age I am "in school". It's
for a good cause - an Instrument rating courtesy of the VA. I have come
across some interesting observations I think worth sharing with my fellow
Pietenpol builders/owners and in general to the Experimental home builder
community as a whole. I have a request that you all think about safety and
perhaps post your thought on how we all can increase safety while flying and
for some of us, building.
After reading 50+ NTSB Pietenpol accident reports (2012 all the way to
1970s), it's my novice opinion that the predominant Pietenpol accident CAUSE
is "failure to control the aircraft" in either take-off or landing phase,
usually RESULTS in a stall, stall/spin, hard landing, impact with trees,
failure to maintain directional control after landing, and ground loops.
HIDDEN in these reports is overloaded aircraft unable to climb due to
several "contributing factors" such as density altitude, exceeding the
aircraft gross weight abilities and aircraft loaded outside their CG limits.
Gusty conditions are commonly cited as contributing factors. Every one of
these accidents is human error.
The seconds leading CAUSE of accidents is "Fuel Starvation". In three
cases carb icing was determined to be the likely cause, but is never proven
to be the cause as it "flees the scene of the accident". In a recent
accident (2011) the NTSB stated the cause of the accident was water In the
fuel. In another, the tank was improperly built - the internal finger
strainer was placed over the sump outlet not the supply to the carb and some
"Teflon thread tape" was found blocking the fuel supply inlet to the carb.
In another, the tank vent was blocked by a wasp nest. My favorite of ALL
involves a guy who hand props his engine. The fuel shut off valve is in the
front cockpit (reachable during hand propping). The pilots "NORMAL
PROCEDURE" is to close the fuel valve, prop the engine, then opens the fuel
valve after engine startup. Problem this particular day was he left the
fuel valve closed and when the engine quit during the flight, he could not
reach the fuel valve to open it - it was in the front cockpit! Every one of
these accidents is human error.
Not listed as fuel starvation, one poor guy ran out of fuel in cruise and
made a successful landing off airport in a field with short "ankle length"
grass. He re-filled with 4.5 gallons fuel. On takeoff the left wheel
struck a small rock and the gear collapsed.
I read four accident reports where BUZZING was the CAUSE of the accident .
Contributing to these accidents are things like flying into a pole at 30 ft
AGL, one into a power line, one from a downdraft, and one from failure to
maintain air speed. Every one of these accidents is human error. Four
accidents and 5 fatalities!
The stall/spin on landing or takeoff and BUZZING are the predominant CAUSE
of fatal accidents.
Next come propellers (everyone pay attention!). There are two known
accidents caused by in-flight separation of the propeller (both Fords). In
both cases many (but not all) prop hub bolts had sheared indicating improper
inspections of the propeller, bolts, and hub. Rust was visible on the
sheared portion of the bolts. The third case involved a homemade prop that
failed to provide adequate thrust and the plane crashed on takeoff (actually
the pilot crashed the plane, not the other way around). Every one of these
accidents is human error.
Now here is one that will give those who asked about putting controls up
front will like to hear about - 3 accidents in all. In one accident, the
front passenger inadvertently pulled the throttle closed and the pilot was
unable to overcome the passengers "death grip" on the throttle - they
crashed. In another case, the passenger inadvertently applied left aileron
(with his legs when he turned around to look at the pilot) during a
"upsetting" takeoff, the pilot could not recover in time and they crashed.
Finally in a third incident a seat cushion was interfering with the rudder /
brakes. The preflight did not notice this condition and the pilot crashed
on takeoff. Every one of these accidents is human error .
Notice, I have not yet made mention of any mechanical engine issues so far?
Well there are a couple unrelated accidents, where "loss of engine power"
(not attributed to carb ice) was listed as a contributing factor but NEVER
the CAUSE of the accident (just as in the case of carb ice). In all these
cases "failure to maintain control of the aircraft" was the CAUSE. One
case cited a burnt exhaust valve, and another was "overheating" related to a
blockage of the oil cooler caused oil starvation - ironically the foreign
object was part of a cylinder ring. In a third case "CAUSE UNKNOWN"
resulting in a loss of power. Noted in this case was low compression in 3
of the 4 cylinders. And finally a "burred" carb needle caused the needle
to stick in the closed position (on landing - pilot needed power and did not
get it). Every one of these accidents was CAUSED by human errors.
The very oldest Pietenpol accident reports (1970s) available on line contain
only a few brief words in the accident report. One mentions improper
rigging of a turnbuckle. It broke in fight, the wing shifted and the CG was
disturbed. In another, the "push-pull" rod failed at the bell crank. Both
of these accidents resulted in fatalities. All caused by human error.
Now I am sure there are numerous Pietenpol accidents that did not show up in
the 50+ NTSB Pietenpol accident reports I was able to obtain. I suspect
this because I could not find reports on notable and known accidents of
certain non Pietenpol accidents I wanted to research. But I think it's fair
to say that MOST Pietenpols are inherently safe - because of the design and
because of the builder/owner/pilot. In my novice opinion, It's the pilot
and the "maintainer" that you need to be keeping an eye on to prevent
accidents.
Summation: Most accidents are the result of a chain of events. Normally it
requires only one link in the chain to be broken to avoid an accident. What
accident chain links can you break? ALL of them!
Our Pietenpol "type club" needs to do a better job to prevent accidents. I
suggest the following:
. Better pre-flight inspections with strict adherence to checklists
would have avoided MANY of these accidents.
. Not flying aft of the rear CG limits would have avoided MANY of
these accidents - those of us still building MUST not skip the W&B step at
the end of construction!
. Use of carb heat might have avoided several accidents. Always use
carb heat when power is below cruise setting! Make this a checklist item.
. Avoiding BUZZING would definitely have prevented fatal accidents -
Don't do it!
. Adequate training / experience handling difficult landing and
takeoff conditions. Consider not flying in gusty conditions with passengers
- or at all.
. Better passenger briefing and perhaps requiring usage of an
intercom/headsets to communicate with the passenger should be mandatory
. I suggest passenger placing their hands on the outboard fuse walls
(9 and 3 o'clock) during takeoffs and landings to be part of your
checklists.
. Make front stick removable and keep it uninstalled in most
instances.
. Do a Weight & Balance of the airplane - know your true CG data -
and keep within it.
. Consider Density altitude, gross weight and performance when
taking a passenger
. Pay better attention to slow flight stall/spin avoidance
procedures - takeoffs and landings
WHAT DO YOU SUGGEST we do to make flying our Pietenpol safer?
Bob Dewenter
Piet builder / Corvair owner
Dayton OH
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Glad you read all those NTSB reports Bob and improving our safety record is
a commendable effort for sure but
the NTSB and FAA don't classify homebuilts the same in their records/report
s so analyzing the data can be a muddy
endeavor. (still it is pretty clear what factors cause the most trouble f
or hombuilders/pilots like us)
Ron Wanttaja put together this great report explaining some differences in
the way homebuilt
accidents are tabulated by cause and even includes some comparisons with fa
ctory built GA airplanes.
Worth a look really and he summarizes things nicely.
http://www.eaa.org/news/2010/homebuilts_report_wanttaja.pdf
Mike C.
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Subject: | Re: How do we increase safety? |
GREAT post and great reading. These are manmade machines, in a way, you can without
investigating ALWAYS say it's human error. However, except in a general
way, that's not very useful.
Knowing WHAT the human did wrong, is THE BEST information. It's not very useful
to say, (and related to the Lowe's steel debacle) use good materials, use good
craftsmanship, use accepted practices and exercise perfect judgment ALL THE
TIME.
I like your list at the end of the post and is a great starting point. They address
certain more commonly goofed SPECIFIC items. I have several things to add
to the list, learned the hard way, and I'll do that later.
For now, all I have to add is a philosophy I used when I was the Aviation Safety
Officer of VT7 in Meridian MS in the late 90's. Us typical type A overachieving
mathematical types are easily defeated by saying it's obvious you CAN NOT
have a perfect safety record, so what's the point?
I used to remind everyone in the squadron that that fact was absolutely true, so
don't even bother with the Navy's safety record, just their own... Very few
guys were willing to believe that they couldn't do that!
Semantics for sure, but seemed to put things in perspective.
I do have one disagreement, I believe ALL accidents are a result of a chain, not
most. Theoretically not true I'm sure, but probably closer than "most"! Aviation
Safety Officer school was SIX WEEKS of learning how all our buddies morted
themselves, it was morose and depressing. That "chain" is the subject of
practically ALL safety discussions and a super useful thing to understand in safety
awareness.
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Subject: | Re: How do we increase safety? |
Just curious as to what is not useful about saying "use good materials", and "use
good craftsmanship", and "use accepted practices" ALL THE TIME. While it simply
isn't possible to exercise *perfect* judgment ALL THE TIME, it IS possible
to exercise GOOD judgement all the time.
Bill C.
> It's not very useful to say, (and related to the Lowe's steel debacle) use good
materials, use good craftsmanship, use accepted practices and exercise perfect
judgment ALL THE TIME.
>
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Subject: | Re: How do we increase safety? |
Well, all of those things can be done all the time, but that they're not to a degree
it's worth talking about leads me to believe it's just vague enough to warrant
a closer more relevant look. Making it not very useful as a general statement.
What materials are most commonly used that are unsafe?
What judgment errors are most commonly made with a Pietenpol?
What unsafe practices are generally committed with high frequency?
If we find things that are unique to the Piet, ie are more people committing errors
associated with density altitude with a Piet than a GA aircraft that has
published tables (but the same genre, ie a Cub), maybe we've found something relevant.
Something not likely to be found by simply saying, "don't operate your
plane outside it's performance envelope", which itself is more specific than
saying "don't commit an error in judgment.
One could have an entire world wide encompassing safety program with one phrase.
"Don't do anything unsafe..." That's been proven to be not very useful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=392966#392966
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Subject: | Re: How do we increase safety? |
All good points to consider but that brings up a series of other questions - perhaps
answered elsewhere. For instance; How do you go about developing your own
"performance envelope" in a manner that keeps you safe and not putting yourself
and your aircraft in danger? I know that this is part of what the 40-hour
(for most of us) fly-off period is supposed to be for. Is there a published
method for coming up with all the required "V" speeds and such?
Tom Stinemetze
N328X
>>> "tools" <n0kkj@yahoo.com> 1/23/2013 3:19 PM >>>
Well, all of those things can be done all the time, but that they're not to a degree
it's worth talking about leads me to believe it's just vague enough to warrant
a closer more relevant look. Making it not very useful as a general statement.
What materials are most commonly used that are unsafe?
What judgment errors are most commonly made with a Pietenpol?
What unsafe practices are generally committed with high frequency?
If we find things that are unique to the Piet, ie are more people committing errors
associated with density altitude with a Piet than a GA aircraft that has
published tables (but the same genre, ie a Cub), maybe we've found something relevant.
Something not likely to be found by simply saying, "don't operate your
plane outside it's performance envelope", which itself is more specific than
saying "don't commit an error in judgment.
One could have an entire world wide encompassing safety program with one phrase.
"Don't do anything unsafe..." That's been proven to be not very useful.
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Subject: | Re: How do we increase safety? |
> Is there a published method for coming up with all the required "V" speeds and
such?
AC90-89A
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The common wisdom I subscribe to is:
Flying is about as dangerous as riding a motorcycle. The Insurance rates are about
the same. Insurance companies do the math.
To reduce your accident/death rate stay away from the following:
Drinking or drugs) and flying
VFR Flying into IFR
doing aerobatics in a non aerobatic plane,
radical showing off down low.
not wearing the proper safety gear.
fly sick.
Not staying or getting current with an instructor.
poor maintenance.
Granted you can have accidents that are not in those categories, but you significantly
reduce your accident rate if you stay away from these activites. I am
willing to take the residual risk for the joy of flying.
Blue Skies,
Steve D
----- Original Message -----
From: "Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]" <michael.d.cuy@nasa.gov>
Subject: Pietenpol-List: safety?
> Glad you read all those NTSB reports Bob and improving our safety
> record is a commendable effort for sure but
> the NTSB and FAA don't classify homebuilts the same in their
> records/reports so analyzing the data can be a muddy
> endeavor. (still it is pretty clear what factors cause the most
> trouble for hombuilders/pilots like us)
>
>
> Ron Wanttaja put together this great report explaining some
> differences in the way homebuilt
> accidents are tabulated by cause and even includes some
> comparisons with factory built GA airplanes.
> Worth a look really and he summarizes things nicely.
>
> http://www.eaa.org/news/2010/homebuilts_report_wanttaja.pdf
>
>
> Mike C.
>
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Subject: | Re: How do we increase safety? |
Thank you Bill! Just what I was needing.
Stinemetze,
N328X
>>> "BYD" <billsayre@ymail.com> 1/23/2013 4:17 PM >>>
> Is there a published method for coming up with all the required "V" speeds and
such?
AC90-89A
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Subject: | Re: Cross wind component |
I agree w/last two posts. Spot on. I got "caught" coming back to home airfeld w/25kts
direct x-wind (sans gusts) and it gets your attention on downwind(and then
on final) when you see the crab angle required. I was quite surprised at how
well it handled troughout landing/rollout. I just bugged it up 10 on final,
de-crabbed last 10 feet, Hoovered it on the upwind wheel, and as the downwind
wheel touched..."tap".."tap" on downwind heel brake to counter the weathervane
into wind....seemed to work ok (GN-1/A65). I was about to go try it again, but
thought it best not to press my good fortune..
15 plus Knots and "gusting" ... I'd rather take the 25 Knotter w/out the gusts.
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Subject: | How do we increase safety? |
Thanks for that synopsis, Bob. Unfortunately, all these causes of accidents
are not limited to Pietenpols only. All of general aviation suffers these,
with experimental aircraft showing up in these statistics a
disproportionately high number of times.
I like your list of bulletpoints at the bottom. I particularly like your
last suggestion. As a CFI, whenever I'm doing a flight review for a private
pilot, I always have him/her go through a series of power-off and power-on
stalls, as well as demonstrating turns in slow flight. I also like to pull
the power at some point to simulate an engine failure and determine if they
are able to correctly pick a suitable landing field and set up an approach
to it. Then when we are on downwind leg in the traffic pattern, I'll pull
it again and tell them to make the runway and land without touching the
throttle. I'm always amazed at the wide patterns people fly, and then
wonder why they can't make the field when the engine quits.
A Pietenpol is a very safe airplane, but it does have its quirks. Chief
among them is the high drag inherent to the design, with the resulting poor
glide ratio. Trying to "stretch" a glide in a Pietenpol is a sure-fire
recipe for disaster. When flying a traffic pattern in a Piet, you want to
stay very close to the runway on the downwind leg. My personal preference
is to fly the approach a little high, and then when I know I can make the
field, slip it to lose altitude.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
_____
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Robert
Dewenter
Sent: Wednesday, January 23, 2013 1:20 PM
Subject: Pietenpol-List: How do we increase safety?
Fellow Piet builder/ flyers:
A long story would tell you why I signed up for a college course in
aviation accident investigations - and why at my age I am "in school". It's
for a good cause - an Instrument rating courtesy of the VA. I have come
across some interesting observations I think worth sharing with my fellow
Pietenpol builders/owners and in general to the Experimental home builder
community as a whole. I have a request that you all think about safety and
perhaps post your thought on how we all can increase safety while flying and
for some of us, building.
After reading 50+ NTSB Pietenpol accident reports (2012 all the way to
1970s), it's my novice opinion that the predominant Pietenpol accident CAUSE
is "failure to control the aircraft" in either take-off or landing phase,
usually RESULTS in a stall, stall/spin, hard landing, impact with trees,
failure to maintain directional control after landing, and ground loops.
HIDDEN in these reports is overloaded aircraft unable to climb due to
several "contributing factors" such as density altitude, exceeding the
aircraft gross weight abilities and aircraft loaded outside their CG limits.
Gusty conditions are commonly cited as contributing factors. Every one of
these accidents is human error.
The seconds leading CAUSE of accidents is "Fuel Starvation". In three
cases carb icing was determined to be the likely cause, but is never proven
to be the cause as it "flees the scene of the accident". In a recent
accident (2011) the NTSB stated the cause of the accident was water In the
fuel. In another, the tank was improperly built - the internal finger
strainer was placed over the sump outlet not the supply to the carb and some
"Teflon thread tape" was found blocking the fuel supply inlet to the carb.
In another, the tank vent was blocked by a wasp nest. My favorite of ALL
involves a guy who hand props his engine. The fuel shut off valve is in the
front cockpit (reachable during hand propping). The pilots "NORMAL
PROCEDURE" is to close the fuel valve, prop the engine, then opens the fuel
valve after engine startup. Problem this particular day was he left the
fuel valve closed and when the engine quit during the flight, he could not
reach the fuel valve to open it - it was in the front cockpit! Every one of
these accidents is human error.
Not listed as fuel starvation, one poor guy ran out of fuel in cruise and
made a successful landing off airport in a field with short "ankle length"
grass. He re-filled with 4.5 gallons fuel. On takeoff the left wheel
struck a small rock and the gear collapsed.
I read four accident reports where BUZZING was the CAUSE of the accident .
Contributing to these accidents are things like flying into a pole at 30 ft
AGL, one into a power line, one from a downdraft, and one from failure to
maintain air speed. Every one of these accidents is human error. Four
accidents and 5 fatalities!
The stall/spin on landing or takeoff and BUZZING are the predominant CAUSE
of fatal accidents.
Next come propellers (everyone pay attention!). There are two known
accidents caused by in-flight separation of the propeller (both Fords). In
both cases many (but not all) prop hub bolts had sheared indicating improper
inspections of the propeller, bolts, and hub. Rust was visible on the
sheared portion of the bolts. The third case involved a homemade prop that
failed to provide adequate thrust and the plane crashed on takeoff (actually
the pilot crashed the plane, not the other way around). Every one of these
accidents is human error.
Now here is one that will give those who asked about putting controls up
front will like to hear about - 3 accidents in all. In one accident, the
front passenger inadvertently pulled the throttle closed and the pilot was
unable to overcome the passengers "death grip" on the throttle - they
crashed. In another case, the passenger inadvertently applied left aileron
(with his legs when he turned around to look at the pilot) during a
"upsetting" takeoff, the pilot could not recover in time and they crashed.
Finally in a third incident a seat cushion was interfering with the rudder /
brakes. The preflight did not notice this condition and the pilot crashed
on takeoff. Every one of these accidents is human error .
Notice, I have not yet made mention of any mechanical engine issues so far?
Well there are a couple unrelated accidents, where "loss of engine power"
(not attributed to carb ice) was listed as a contributing factor but NEVER
the CAUSE of the accident (just as in the case of carb ice). In all these
cases "failure to maintain control of the aircraft" was the CAUSE. One
case cited a burnt exhaust valve, and another was "overheating" related to a
blockage of the oil cooler caused oil starvation - ironically the foreign
object was part of a cylinder ring. In a third case "CAUSE UNKNOWN"
resulting in a loss of power. Noted in this case was low compression in 3
of the 4 cylinders. And finally a "burred" carb needle caused the needle
to stick in the closed position (on landing - pilot needed power and did not
get it). Every one of these accidents was CAUSED by human errors.
The very oldest Pietenpol accident reports (1970s) available on line contain
only a few brief words in the accident report. One mentions improper
rigging of a turnbuckle. It broke in fight, the wing shifted and the CG was
disturbed. In another, the "push-pull" rod failed at the bell crank. Both
of these accidents resulted in fatalities. All caused by human error.
Now I am sure there are numerous Pietenpol accidents that did not show up in
the 50+ NTSB Pietenpol accident reports I was able to obtain. I suspect
this because I could not find reports on notable and known accidents of
certain non Pietenpol accidents I wanted to research. But I think it's fair
to say that MOST Pietenpols are inherently safe - because of the design and
because of the builder/owner/pilot. In my novice opinion, It's the pilot
and the "maintainer" that you need to be keeping an eye on to prevent
accidents.
Summation: Most accidents are the result of a chain of events. Normally it
requires only one link in the chain to be broken to avoid an accident. What
accident chain links can you break? ALL of them!
Our Pietenpol "type club" needs to do a better job to prevent accidents. I
suggest the following:
* Better pre-flight inspections with strict adherence to checklists
would have avoided MANY of these accidents.
* Not flying aft of the rear CG limits would have avoided MANY of
these accidents - those of us still building MUST not skip the W&B step at
the end of construction!
* Use of carb heat might have avoided several accidents. Always use
carb heat when power is below cruise setting! Make this a checklist item.
* Avoiding BUZZING would definitely have prevented fatal accidents -
Don't do it!
* Adequate training / experience handling difficult landing and
takeoff conditions. Consider not flying in gusty conditions with passengers
- or at all.
* Better passenger briefing and perhaps requiring usage of an
intercom/headsets to communicate with the passenger should be mandatory
* I suggest passenger placing their hands on the outboard fuse walls
(9 and 3 o'clock) during takeoffs and landings to be part of your
checklists.
* Make front stick removable and keep it uninstalled in most
instances.
* Do a Weight & Balance of the airplane - know your true CG data -
and keep within it.
* Consider Density altitude, gross weight and performance when
taking a passenger
* Pay better attention to slow flight stall/spin avoidance
procedures - takeoffs and landings
WHAT DO YOU SUGGEST we do to make flying our Pietenpol safer?
Bob Dewenter
Piet builder / Corvair owner
Dayton OH
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