Prop Strikes
selw...@yahoo.com
Mine have been ag related and hit ground, rocks, birds, and ?
Ever throw off a piece of the prop blade? I lost a piece during
climbout of a jungle strip in the Amazon in a C-185. Managed to dead
stick it back without any further damage but it took nearly two months
to get a replacement. IN the meantime, I used a field expedient and cut
off an equal amount from the other blade. We were about 200 miles from
civilization on the Rio Curaray.
Ah the fun old days....
Ol S&B
Larry Dighera
<1106695204.9...@z14g2000cwz.googlegroups.com>::
>Anyone else here ever experience one?
Sort of.
>How did yours happen?
After a buffalo burger on Santa Catalina Island, I telephoned SoCal
TRACON and filed IFR back to the mainland. After performing a walk
around inspection I got into the aircraft, and my flight instructor
pulled the aircraft out of the rough onto the asphalt, and climbed in
behind me (PA28).
We went through the prestart checklist, and I engaged the starter only
to hear a loud clunk as the first blade went by. He had left the tow
bar on the front gear leg. :( He was a little chagrined, but there
was no damage, so we released within our time window for an uneventful
flight home.
George Patterson
selw...@yahoo.com wrote:
>
> Anyone else here ever experience one?
Not yet.
George Patterson
He who marries for money earns every penny of it.
Capt.Doug
> Anyone else here ever experience one? How did yours happen?
Fly long enough and something will hit the fan.
I was taxiing out to the runway after a torrential downpour flooded the
ramp. I taxiied on the high spots at minimum power just in case. At minimum
power (flat pitch) the blade tips are actually causing reverse thrust
because of the twist in the blades. I thought I had missed the standing
water and the plane flew normally for the rest of the day (10 legs).
During a maintenance inspection that evening, I put a protractor on the
blades and they were indeed twisted more than the factory meant for them to
be. I had caught the blade tips in the water and the reverse angle of the
blade tips caused the blades to twist ever so slightly. The prop overhaul
with 4 new blades and an engine gearbox teardown came to around $24k not
including loss of use and the mechanics' salaries. The prop shop mentioned
that if I had not exercised caution by using minimum power, the blade tips
would have been nearly flat and wouldn't have twisted the blades. I've been
careful to be uncareful ever since.
D.
Peter R.
> selw...@yahoo.com wrote:
> >
> > Anyone else here ever experience one?
>
> Not yet.
Two types of pilots, those that have and those that will?? :)
--
Peter
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George Patterson
"Peter R." wrote:
>
> Two types of pilots, those that have and those that will?? :)
I certainly hope not.
Dan Thompson
had to land on the mains. Will never forget the tick-tick-tick of the prop
tips on the concrete. Or the short rollout. Or the jaunty angle when
deplaning.
<selw...@yahoo.com> wrote in message
news:1106695204.9...@z14g2000cwz.googlegroups.com...
John Godwin
news:1106695204.9...@z14g2000cwz.googlegroups.com:
> Anyone else here ever experience one?
Yeh.
> How did yours happen?
The airport decided to construct a concrete drainage depression across
the taxiway.
Cub Driver
>Anyone else here ever experience one? How did yours happen?
My instructor was explaining how to make a wheel landing. I just
planted the thang too dang hard. I heard this whup! but we both
thought it was just the bungee cords complaining: it was a very firm
landing.
"I'll take it around, and you follow me on the controls," says he.
So we did. Then I taxied up to the pump and shut down, and I tell you,
it is a sinking feeling to gaze at your prop and notice that the ends
have somewhat melted and are curving in toward the cockpit.
There wasn't the slightest vibration, or loss in performance that
either of us noticed on that last circuit.
No damage to the engine, and as commander of the aircraft, the
instructor's insurance company had the privilege of paying for the
prop.
My technique has improved a lot since then.
-- all the best, Dan Ford
email war...@mailblocks.com (put Cubdriver in subject line)
Warbird's Forum: www.warbirdforum.com
Piper Cub Forum: www.pipercubforum.com
the blog: www.danford.net
John T Lowry
My prop strike was in an ultralight, an Sorrell SNS-8, in Billings. I
was practicing short field landings (for going into rancher friends'
strips) and braked too hard. Slowly...over it went. Cost about $500 in
(2-cycle) engine repairs, plus a new prop.
John Lowry
Flight Physics
Jay Honeck
> to hear a loud clunk as the first blade went by. He had left the tow
> bar on the front gear leg. :(
I saw a guy do that once.
Hitting the tow bar may not damage the prop, but it sure would damage
whatever the tow bar hit. In the case I witnessed, the prop whipped the tow
bar into the adjacent hangar wall with surprising force. It was only luck
that kept it from hitting a car or bystander.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"
Dudley Henriques
"Cub Driver" <war...@mailblocks.com> wrote in message
news:djrev09oinb7fdb3m...@4ax.com...
> On 25 Jan 2005 16:11:39 -0800, selw...@yahoo.com wrote:
>
>>Anyone else here ever experience one? How did yours happen?
>
> My instructor was explaining how to make a wheel landing. I just
> planted the thang too dang hard. I heard this whup! but we both
> thought it was just the bungee cords complaining: it was a very firm
> landing.
>
> "I'll take it around, and you follow me on the controls," says he.
>
> So we did. Then I taxied up to the pump and shut down, and I tell you,
> it is a sinking feeling to gaze at your prop and notice that the ends
> have somewhat melted and are curving in toward the cockpit.
>
> There wasn't the slightest vibration, or loss in performance that
> either of us noticed on that last circuit.
>
> No damage to the engine, and as commander of the aircraft, the
> instructor's insurance company had the privilege of paying for the
> prop.
>
> My technique has improved a lot since then.
As has the instructor's I hope. The decision to go around after he heard
the "whump" was in my opinion anyway, a bad one.
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/CFI Retired
for private email; make necessary changes between ( )
dhenriques(at)(delete all this)earthlink(dot)net
Paul kgyy
Upper Cowl separated on one side on my Arrow in flight - wind blew it
up on the windshield and since the other side remained attached, it
twisted and put about a 1/8 inch dent in the back of both blades.
Mechanic insisted I tear the whole #$&$ engine apart. One blade turned
out to be out of spec, couldn't find replacement 2blade prop, ta da ta
da da da. That's how it goes with airplanes. At least I know the
engine is nice & clean inside and the new 3 blade prop looks nice.
selw...@yahoo.com
In that same vein, with winter conditions, how about the frozen humps
from snow plows that are waiting to get the nose gear struts with
attendant prop strikes or linkage damage?
Owwww
Ol S&B
selw...@yahoo.com
I had a similar landing incident when the very experienced ag pilot in
the front seat "stuck" the aircraft with positive forward stick on
touchdown and put sand marks about 6" up the prop blade and bent the
blades. We didn't follow up with any take off though. He was using his
usual technique of forward stick with the Stearman he had been using
for spraying and this time it didn't work on the Champion Scout we were
flying. I was showing him the aircraft and it was his first flight in
it. There is more to the story and in retrospect it's humorous but
nontheless serious.
Ol S&B
Larry Dighera
<jjho...@NOSPAMmchsi.com> wrote in <q0OJd.29738$EG1.8340@attbi_s53>::
>> We went through the prestart checklist, and I engaged the starter only
>> to hear a loud clunk as the first blade went by. He had left the tow
>> bar on the front gear leg. :(
>
>I saw a guy do that once.
>
>Hitting the tow bar may not damage the prop, but it sure would damage
>whatever the tow bar hit.
We were fortunate. The tow bar remained attached to the gear leg. I
presume this meant that the cylinder failed to fire in the first 180
degrees of prop rotation.
Peter R.
> Anyone else here ever experience one? How did yours happen?
I have not experienced one personally, but a flight instructor and a
student from my flight school had landed at a nearby single strip
airport. Instead of back-taxiing down the runway, they opted to taxi on
the grass, which is actually an adjacent grass strip.
However, at the end of the grass strip they turned the aircraft around
to taxi onto the runway when the nose wheel dropped into a gopher hole.
The prop struck the soft ground but somehow neither student nor
instructor knew of the prop strike until they returned to our main
airport. Regardless of the softness of the ground, an engine tear-down
was needed.
--
Peter
Sam O'Nella
Jim Burns
FAA Inspector is finishing up some business at the FBO when a Mooney taxi's
up and shuts down. Pilot jumps out, storms into the FBO and starts chewing
out the FBO attendant...
"When was the last time anybody checked the runway for FOD?!! I just tried
to take off and I know I ran something over! This airplane cost me $$$$ and
I will not tolerate debris on the runway!!.... blah bla blah... I want to
see the airport manager, I'll have your job.... bla bla bla...
The FAA Inspector just stands back and listens for awhile, then goes out to
secretly investigate... he goes out on the runway and discovers a towbar...
brings it back and approaches an open hanger where another pilot was washing
his plane and asks if he recognizes the towbar... pilot responds "Yep,
that's George's, the guy with the Mooney parked down infront of the FBO"
FAA Inspector takes the towbar back to the FBO and asks the Mooney pilot if
that was his towbar. Mooney pilot says "Yep, and who the hell bent it all
up on me??!! I just used it 20 minutes ago!!"
FAA Inspector says "You did. You taxied out and tried to take off with it
still attached. I'll let you off with some remedial training and by the
way, you'll need a new prop and an engine tear down."
Jim
T-Boy
selw...@yahoo.com says...
First non-solo PPL flight (ie, my very first pax). They've sealed the
area now :) Started the Traumahawk up and taxied carefully over the
side of the undulation (well I thought it was the side, or "side
enough") - and felt a vibration lasting about half a second. I looked
at my pax, they looked at me - carried on. Got radioed by tower 30 sec
later to return to the operator base. Did so - someone had spotted some
grass flying up while I'd taxied and touched and the op radioed tower.
Checked out by the operator LAME and cleared to go. What a start to my
first passenger flight!!!
--
Duncan
Gene Seibel
--
Gene Seibel
Gene & Sue's Aeroplanes - http://pad39a.com/gene/planes.html
Because I fly, I envy no one.
Corky Scott
>In article <1106695204.9...@z14g2000cwz.googlegroups.com>,
>selw...@yahoo.com says...
>> Anyone else here ever experience one? How did yours happen?
Didn't happen to me, saw the airplane in a hangar next to the one I
was working in and asked.
Seems the not very old Cessna 172 was towed out of the hangar by a
friend of owner. This friend had permission to fly it and was an
instructor. The instructor/friend towed the airplane out using a golf
cart they have for the purpose. After pulling the airplane out and
turning it away from the hangar door and aligning it with the taxiway,
the guy disconnnects the golf cart and puts it into the hangar and
closes the hangar door. Then he comes back out and climbs into the
airplane and fires it up.
Nothing happened right away, not at idle anyway. The prop missed the
still attached towbar. But when the engine was revved up for the
runnup, the lowered pressure in front of the prop sucked the tow bar
up and I guess caused a sudden stop.
When I saw the airplane it was without it's engine and prop. The prop
had to be replaced and the engine overhauled. The prop was a constant
speed version. Pretty costly whoops.
Corky Scott
Blueskies
<Scott D.> wrote in message news:uonfv0186u86dtl1i...@4ax.com...
> On Tue, 25 Jan 2005 23:10:02 -0500, Peter R. <prgr...@twcny.rrX.com>
> wrote:
>
>>George Patterson (grpp...@verizon.net) wrote:
>>
>>> selw...@yahoo.com wrote:
>>> >
>>> > Anyone else here ever experience one?
>>>
>>> Not yet.
>>
>>Two types of pilots, those that have and those that will?? :)
>
>
> Scott D
> Scottdsp...@coflying.com
> To email remove spamcatcher
>
>
I think we could safely say that the person that lands gear up will simultaneously experience a prop strike...
Blueskies
crunching and grinding and chunk chunk chunk as the engine died under the load. He knew right where the hole was and was
trying to miss it with his mains...ended up with a new prop and engine...
<selw...@yahoo.com> wrote in message news:1106695204.9...@z14g2000cwz.googlegroups.com...
Icebound
"Gene Seibel" <ge...@pad39a.com> wrote in message
news:1106773097.8...@z14g2000cwz.googlegroups.com...
> Once. http://pad39a.com/gene/flypix0.html
> --
You mention co-coordinating the ailerons with the wind condition, and the
use of power, but you don't mention the use of elevator.
If you were originally (okay) in the quartering tailwind, might you not have
had the elevator full down (forward) as recommended, which would have caused
the tail-lift once in a headwind situation??? (and power would have just
added even more lift to the tail).
Or do you recall pulling the elevator back (up) as you crossed from
tailwind-to-headwind?
Blueskies
"Gene Seibel" <ge...@pad39a.com> wrote in message news:1106773097.8...@z14g2000cwz.googlegroups.com...
Bummer, looked like a nice bird. My first airplane ride was in a TriPacer...
George Patterson
Corky Scott wrote:
>
> Nothing happened right away, not at idle anyway. The prop missed the
> still attached towbar. But when the engine was revved up for the
> runnup, the lowered pressure in front of the prop sucked the tow bar
> up and I guess caused a sudden stop.
Machado tells the story of a plane spotted taxiing with the towbar still
attached. Someone radioed to stop him from taking off.
He had just landed.
Gene Seibel
head. Elevator control was something that simply wasn't instinctive to
me, and it happened in a split second.
Sam O'Nella
necessary afterwards?
Dan Thompson
stoppage. This has never made sense to me from an engineering standpoint.
When the engine is started it goes from barely turning to suddenly spinning
fast. Why can't it take a faster than normal deceleration from a prop
flailing against pavement or bashing a tow bar?
"Sam O'Nella" <son...@gmail.com> wrote in message
news:PJydnQKGILO...@comcast.com...
Sam O'Nella
> Lyc and TCM require it based on possible damage to the engine from a
> sudden stoppage. This has never made sense to me from an engineering
> standpoint. When the engine is started it goes from barely turning to
> suddenly spinning fast. Why can't it take a faster than normal
> deceleration from a prop flailing against pavement or bashing a tow
> bar?
I can see how the impulse decelleration of a strike vastly exceeds that of
normal engine operation.
I could see the crank "twisting" especially if it were pressed together from
separate parts (I have no idea if it is). I'd be interested to know what %
of teardowns after prop strikes actually uncover hidden damage, and what
damage that was.
Dave Butler
> I could see the crank "twisting" especially if it were pressed together from
> separate parts (I have no idea if it is).
On every airplane I know about, the crankshaft is a single monolithic steel
forging. Some are hollow to allow for oil passages.
Frank Ch. Eigler
> Someone please remind me again why a complete engine teardown is
> always necessary afterwards?
During a prop strike, the engine is producing power, yet an external
force is suddenly counteracting it. That leads to conflicting
internal forces that can damage crankshafts, retaining bolts (see a
recent Lycoming AD), probably all sorts of moving things.
- FChE
Hatz Lyman C
>fast. Why can't it take a faster than normal deceleration from a prop
>flailing against pavement or bashing a tow bar?
The difference is whether the acceleration or deceleration is constant or
sudden.
Lyman
Robert A. Barker
"George Patterson" <grpp...@verizon.net> wrote in message
news:41F861A9...@verizon.net...
I watched one take start to take off with the tow bar
attached.It dropped off just as the plane left the ground.
No damage as far as I know.
Bob Barker N8749S
Dan_Thom...@yahoo.com
steel
>forging. Some are hollow to allow for oil passages.
Cranks in radials are pressed together from several pieces. The
master rod can't have the usual split feature since it has pin bosses
all around it for the other connecting rods to attach to.
Any propstrike can cause unseen damage inside the case. I had a
crank break due to a propstike sometime in the undocumented past. It
broke between the rearmost rod throw and the one next ahead, a long way
behind the prop. In small Continentals, this is apparently the usual
place to break. Some guys will dial the prop flange to see if it's
bent, but this doesn't tell you how much it bent and then sprang back.
Cracks can form anywhere in the crank due to twisting and bending
forces, rods can bend or pistons crack, rod bolts stretch and crack or
come loose. A propstrike is a MUCH more rapid decelleration than
spooling down or starting up, however brief it might be. Wooden props
will often spare the engine, metal props are unforgiving. A propstrike
could be a bomb waiting to bite someone later on.
Dan
Julian Scarfe
news:1106695204.9...@z14g2000cwz.googlegroups.com...
> Anyone else here ever experience one? How did yours happen?
Mooney 201 main gear slipped down into a hidden drain while taxying on
grass. The aircraft tipped forward and the prop tip touched the turf. I
still remember the sound. It's a horrible sound... :-(
Julian
Dan Thompson
through a tow bar or digs a little ditch in the dirt. The Lyc and TCM
instructions, however, are that any incident that damages the prop to any
extent that cannot be repaired by simple gravel nick-filing requires a
teardown. Which seems like crazy overkill to me.
I can see that a sudden stoppage, a la WHANG! - (silence), might break
something inside.
"Hatz Lyman C" <hatzl...@aol.com> wrote in message
news:20050127115508...@mb-m12.aol.com...
Dan_Thom...@yahoo.com
and another bent. Bent cranks don't run properly in the bearings,
wearing them rapidly and ultimately resulting in failure. The undamaged
cranks were from more minor propstrikes.
Here's another reason to get it checked: An engine overhaul
shop had a crank with a crack through the front main, caused by a
propstrike. They tossed it into the scrap barrel, where it was spotted
by a guy building up an engine for his homebuilt. He wanted it, they
refused, and it disappeared shortly thereafter. A couple of years later
they heard of this same guy being killed in his homebuilt when the
front of the crank broke off and the prop came through the windshield,
believe it or not, killing him instantly. Investigators found that the
crack in the crank had been welded and remachined.
Dan
Dan
steve
riser out of limits...a nick on the trailing edge would cause a chordwise
crack quite quickly...If i were flying that plane, I would refuse to fly the
aircraft until the prop was certified airworthy by at least a qualified
mechanic. A small scratch may seem irrelevant but at 9000g's it really is.
"Larry Dighera" <LDig...@att.net> wrote in message
news:1qgfv0t3279iamscv...@4ax.com...
steve
"Dan Thompson" <ju...@junk.net> wrote in message
news:oqFJd.24336$iC4....@newssvr30.news.prodigy.com...
>I had two prop strikes on a twin when the nose gear wouldn't come down and
>I had to land on the mains. Will never forget the tick-tick-tick of the
>prop tips on the concrete. Or the short rollout. Or the jaunty angle when
>deplaning.
>
> <selw...@yahoo.com> wrote in message
> news:1106695204.9...@z14g2000cwz.googlegroups.com...
>> Anyone else here ever experience one? How did yours happen?
Dan Thompson
Also I didn't belly in. Landed on mains only. Used the nose as a skid.
Big difference.
"steve" <swr...@hotmail.com> wrote in message
news:ULfKd.1851$Sx6....@read2.cgocable.net...
Roger
<grpp...@verizon.net> wrote:
>
>
>Corky Scott wrote:
>>
>> Nothing happened right away, not at idle anyway. The prop missed the
>> still attached towbar. But when the engine was revved up for the
>> runnup, the lowered pressure in front of the prop sucked the tow bar
>> up and I guess caused a sudden stop.
>
>Machado tells the story of a plane spotted taxiing with the towbar still
>attached. Someone radioed to stop him from taking off.
A few years back, Joyce and I were headed over to Vassar MI from 3BS.
On the way we heard a guy in a Grumman Tiger ask a guy if he was in
the area. Hearing an affirmative he asked if the other plane could
join up with him. A different voice asked, "Forget something?".
There was a pause and as I recall the answer was, "Ahhhh Maybe".
Other voice, "something like a tow bar maybe?". Answer, "Not sure".
The second plane joined up and sure enough, "You have something
hanging from the nose gear. Kinda looks like a tow bar.
So, he headed back to Harry Brown airport. He set it down nice and
easy and the tow bar just skidded along. They removed the tow bar and
he went back out.
>
>He had just landed.
I think I remember hearing some one radio this guy when he was on the
ground to tell him he still had the tow bar attached and to not take
off. He too, told them he'd just landed.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
Roger
wrote:
>
>Upper Cowl separated on one side on my Arrow in flight - wind blew it
>up on the windshield and since the other side remained attached, it
>twisted and put about a 1/8 inch dent in the back of both blades.
>Mechanic insisted I tear the whole #$&$ engine apart. One blade turned
As I recall, any strike that requires more than a minor dressing
requires an engine tear down according to Lycombing and Continental.
>out to be out of spec, couldn't find replacement 2blade prop, ta da ta
>da da da. That's how it goes with airplanes. At least I know the
>engine is nice & clean inside and the new 3 blade prop looks nice.
Roger
>Once. http://pad39a.com/gene/flypix0.html
When I was a primary student my instructors (two) did not figure any
wind less than the airplanes capabilities was an excuse for canceling.
I hated it at the time, but I was thankful they put me through that
when I did my first long cross country. A bunch of lake effect snow
storms popped up between "the straights" and TVC. Had I not been
thoroughly tested in those conditions it would have scared the crap
out of me.
My biggest fear was the wind getting under the tail when headed for
the transient parking ramp and doing what it did to you.
Blueskies
"Gene Seibel" <ge...@pad39a.com> wrote in message news:1106802348.7...@f14g2000cwb.googlegroups.com...
Tricycle gear while taxiing; always dive into the wind or dive away from it...
Newps
steve wrote:
> Hitting the tow bar would damage the prop enough to put any nick or stress
> riser out of limits...a nick on the trailing edge would cause a chordwise
> crack quite quickly...If i were flying that plane, I would refuse to fly the
> aircraft until the prop was certified airworthy by at least a qualified
> mechanic. A small scratch may seem irrelevant but at 9000g's it really is.
>
Bah, buddy of mine has a J5. He taxiied into a huge hole one day. Bent
the prop on both ends. We found a couple of wooden chocks and a big
mallet. We beat the prop back straight, more or less. He flew it home
and let the prop shop overhaul it. Sure it vibrated a little bit, but
it's a cub.
Larry Dighera
>"Larry Dighera" <LDig...@att.net> wrote in message
>news:1qgfv0t3279iamscv...@4ax.com...
>> On Wed, 26 Jan 2005 14:43:35 GMT, "Jay Honeck"
>> <jjho...@NOSPAMmchsi.com> wrote in <q0OJd.29738$EG1.8340@attbi_s53>::
>>
>>>> We went through the prestart checklist, and I engaged the starter only
>>>> to hear a loud clunk as the first blade went by. He had left the tow
>>>> bar on the front gear leg. :(
>>>
>>>I saw a guy do that once.
>>>
>>>Hitting the tow bar may not damage the prop, but it sure would damage
>>>whatever the tow bar hit.
>>
>> We were fortunate. The tow bar remained attached to the gear leg. I
>> presume this meant that the cylinder failed to fire in the first 180
>> degrees of prop rotation.
>>
>
in <EFfKd.1849$Sx6....@read2.cgocable.net>::
>Hitting the tow bar would damage the prop enough to put any nick or stress
>riser out of limits...a nick on the trailing edge would cause a chordwise
>crack quite quickly...If i were flying that plane, I would refuse to fly the
>aircraft until the prop was certified airworthy by at least a qualified
>mechanic. A small scratch may seem irrelevant but at 9000g's it really is.
We examined the prop and the tow bar and were unable to discern any
nick, scratch nor evidence of any impact at all. Of course the
trailing edge of the propeller wasn't involved in our incident.
If you consider that a 4-stroke IC engine requires two revolutions to
complete one full combustion cycle, then it would seem there is one
cylinder firing each half turn of a four cylinder engine.
Fortunately it was just the power of the starter motor that powered
the propeller that (probably less than) half turn. If the engine had
been running or even if it had fired a cylinder in that first 180
degrees, we would have considered scrubbing the flight.
Incidentally, what's a "stress riser?"
Tony Cox
news:1106695204.9...@z14g2000cwz.googlegroups.com...
> Anyone else here ever experience one?
I had one while returning to Boulder City about 3 years
ago. It was early in the afternoon in late May & the winds
were out of the south at about 15 knots. The ride was smooth,
so I didn't expect gusts (big mistake). Landing on the 3 degree
downhill runway 15 with a 7 knot right crosswind was pretty standard,
but during the roll-out while braking hard the wind shifted and
lifted up the left wing. I thought at first I must have scraped the
right wing, but what actually happened is that the plane (182) rotated
about the right main/nose wheel axis sufficiently for the prop tip
to touch the tarmac. Clearing the runway, the automated unicom
was reporting winds as 090@20 with wind shear. The insurance
company (USAIG) were very nice about it & handled the tear-down
& new prop to the tune of about $15K, and without increasing my
premium subsequent years. During the tear-down, discovered
problems with the crank shaft (which may have been caused by
the strike) and some AD's which hadn't been complied with on
the counterweights.
Here's what I learned from that.
1) If it's hot in the desert southwest, always expect wind shear.
Be prepared to adjust the ailerons as necessary & don't just
throw the yoke over to whatever side you think the crosswind
is coming from.
2) Maintain back pressure when on the roll-out especially when
braking hard.
3) Bring up the flaps (they were at 40 degrees) during the
roll-out to make yourself a smaller target for the wind.
Larry Dighera
<0AhKd.7938$r27....@newsread1.news.pas.earthlink.net>::
>
>Here's what I learned from that.
>
>1) If it's hot in the desert southwest, always expect wind shear.
>Be prepared to adjust the ailerons as necessary & don't just
>throw the yoke over to whatever side you think the crosswind
>is coming from.
Actually, it is more appropriate to "steer" with the wind rather than
into it to minimize its effect. That is, if the aircraft is for
example experiencing wind from the right rear, one would push the
yoke/stick forward and to the left. This lowers the elevator and
right aileron, so that the wind can't get under them as easily.
>2) Maintain back pressure when on the roll-out especially when
>braking hard.
That's what the POH recommend, IINM.
>3) Bring up the flaps (they were at 40 degrees) during the
>roll-out to make yourself a smaller target for the wind.
It also puts more weight on the main gear tires to increase brake
effectiveness.
Dan_Thom...@yahoo.com
"field-repaired" prop throws a chunk of blade and tears the engine off
its mounts. Or later, when that almost-certainly cracked crank fails.
As I said in another post, the small Continentals are prone to crank
cracking after prop strikes. Anything violent enough to bend a prop
warrants investigation.
Dan
Tony Cox
> On Fri, 28 Jan 2005 02:37:48 GMT, "Tony Cox" <t...@coxrt.com> wrote in
> <0AhKd.7938$r27....@newsread1.news.pas.earthlink.net>::
>
> >
> >Here's what I learned from that.
> >
> >1) If it's hot in the desert southwest, always expect wind shear.
> >Be prepared to adjust the ailerons as necessary & don't just
> >throw the yoke over to whatever side you think the crosswind
> >is coming from.
>
> Actually, it is more appropriate to "steer" with the wind rather than
> into it to minimize its effect. That is, if the aircraft is for
> example experiencing wind from the right rear, one would push the
> yoke/stick forward and to the left. This lowers the elevator and
> right aileron, so that the wind can't get under them as easily.
The problem, of course, is how do you *know* the wind is
coming from the right rear? I was taught to throw the yoke
over when on the ground, but that presupposes that the
wind is still coming from the same direction as when you
were coming down final. I certainly didn't expect the wind
to go from a 30 degree right x-wind to a 90 degree left
x-wind in the time it takes me to roll out! Live and learn,
eh?
>
> >2) Maintain back pressure when on the roll-out especially when
> >braking hard.
>
> That's what the POH recommend, IINM.
Indeed. And I've replaced my previous limp-wristed gentle
tug with something more akin to reigning in a panicked horse!
As I say, live and learn.
>
> >3) Bring up the flaps (they were at 40 degrees) during the
> >roll-out to make yourself a smaller target for the wind.
>
> It also puts more weight on the main gear tires to increase brake
> effectiveness.
I've always been nervous touching the flaps on landing. Mainly
because of flight instructors who have cautioned against
unnecessary distractions until clear of the runway and others
who think it establishes a bad habit which may come back to
bite if landing in a retractable (confusing flaps with gear). Not
so nervous now...
Gene Seibel
Allen
"Blueskies" <nospamed...@ameritech.net> wrote in message
news:hEgKd.13658$Vj3....@newssvr17.news.prodigy.com...
Bank into a quartering headwind, neutral elevator; dive away from a
quartering tailwind .
Capt.Doug
I'll go >buy an LA-4.
LA-4s suffer prop strikes too. The prop strikes the upper fuselage skin.
D.
Samuel Nella
Under what circumstances does this happen?
Dan_Thom...@yahoo.com
A stress riser is any flaw in a structural piece that concentrates
the stresses through that area to the point that failure might occur. A
common example is cutting glass. The "cutter" doesn't cut; its small
roller causes a shallow crack in the glass that will allow you to break
the glass cleanly when it's bent. On a propeller a nick intereferes
with the lines of force in the blade, causing them to have to bend
around the nick and so concentrating them below the damage. Their
concentration can start the propeller cracking. The blade undergoes
huge G forces outward, thrust forces forward, and drag forces
chordwise; a prop is often the most heavily stressed part on the whole
airplane, and I often see chewed-up props on otherwise cared-for
airplanes.
Owners don't understand the risks. A prop that throws a foot or so
of blade is liable to tear the engine out of the mounts before the
pilot can get it stopped, and guess what happens to the CG when about
300 pounds of engine and prop leave a 172? The airplane can't even
glide.
I demonstrate the stress riser phenomenon to my class using
strips of light aluminum flashing. The students try (unsuccessfully) to
tear a piece of the flashing. Then I file a tiny nick in the edge, and
it tears easily. A second piece with a nick dressed out becomes
impossible to tear.
Dan
nrp
> airplane,
>From an engineering standpoint -
A light plane propeller, whether wood or aluminum, is about 1/8 inch
larger in diameter at cruise than when standing still due to
centrifugal acceleration. Consider also that a prop is an essential
non-redundant monolithic structure, which if aluminum, is made of a
material (2024-T3) that has good tensile, but mediocre fracture
toughness properties. In operation it is subject to very high-cycle
bending fatigue due to torsional resonances.
Fracture toughness is a measure of the crack propagation resistance of
a material. As a fracture toughness example, compare the tensile
strength of cellophane vs shrinkwrap with and without a tiny transverse
slot cut into it.
Props are highly stressed and must not be treated casually.
Dan_Thom...@yahoo.com
>non-redundant monolithic structure, which if >aluminum, is made of a
>material (2024-T3) that has good tensile, but >mediocre fracture
>toughness properties.
Lightplane props are universally made of 2025T6, according to my
Sensenich prop manual. 2024T3 is used mostly for aircraft skins. The
2025 lacks the manganese and magnesium of the 2024, but has silicon
that the 2024 doesn't have. The yield and tensile strengths of 2025T6
are a bit less than 2024T3, but the metal isn't as hard, likely
reducing crack tendencies somewhat. The copper is still present, making
the prop corrosion-prone, and in Canada, at least, we have to remove
the prop, strip it and inspect it for corrosion at least every five
years. Corrosion pits can be as bad as nicks for starting cracks.
Dan
nrp
> Lightplane props are universally made of 2025T6,
The drawing I saw was 2024 (& I recalled T3) but it was not a Sensenich
drawing.
I never heard of 2025 before, though since they are a forged blank,
they could create any alloy........ I originally thought they used
2017.
Big John
I've see reports of a belly landing in a twin where the Pilot shut the
engines down on final and used the starters to turn the props
horizontal. Belly landing did not cause any prop or engine damage.
In fact bird was lifted and gear extended and locked down. FAA gave a
one time permit and bird was flown with gear down to home base for the
minor repair to gear and belly skin.
Big John
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On Thu, 27 Jan 2005 19:34:43 -0500, "steve" <swr...@hotmail.com>
wrote:
Dan Youngquist
> I've see reports of a belly landing in a twin where the Pilot shut the
> engines down on final and used the starters to turn the props
> horizontal. Belly landing did not cause any prop or engine damage.
I've read of guys killing themselves & passengers that way, because they'd
never practiced engine-out landings, or because they got too slow trying
to stop the prop(s), and stalled on final. So whatever you plan to do,
just make sure you practice it safely before you have to do it for real.
-Dan
selw...@yahoo.com
I'd like to think pilots would have the sense to do those things at
altitude? But, I've seen experienced pilots do dumb things from on the
ground all the way up to above FL 180.
Ol S&B
Capt.Doug
Usually during hard landings, when the airframe flexes and the engine pylon
rocks backwards.
D.
selw...@yahoo.com
In the late 60's, a student of mine who bought a Lake Dealership had me
flying with him for his private certificate. We went to the factory
where I got a good checkout and gave my student a lot of dual in his
brand new LA-4. He had some problems landing on water and I told him he
needed to keep his wings level when he touched down on water. He didn't
pay that much attention apparently since one day he tried to do a
"short water" approach and touched down with his wing down. It tore off
the wing sponson, dug the wingtip into the water and cartwheeled the
airplane. After all was said and done, the engine pylon had buckled
over and the prop nearly cut the empanage in half. He survived the
crash with no more than a cut on his forehead and bruises. I
participated in the salvage of the aircraft at 40' depth in a lake in
Louisiana. After his impact, he called on 122.8...."Concordia Unicom
come in quick and I'm not kidding...." then the airplane sank. He was
able to walk off the wing onto a speedboat that had been pulling water
skiiers, tied a float onto the rear tiedown point just as the Lake
Amphibian rolled over and sank inverted. I'ved got photos around here
someplace....
mike regish
cause a major failure. They can be filed out so that they don't form sharp
angles and thus redistribute the stress over a wider area.
I had a small ding on the "back" of my prop (the side you see when you're
looking at the nose from in front of the plane). During an assisted annual,
I filed it out so that it's now a smooth "dent". It has no sharp corners or
edges now.
mike regish
mike regish
student how much the most expensive plane he would ever fly would cost.
After the student giving him prices of Lear jets and Citations Rod said
"Wrong. The most expensive plane you'll ever fly is about $1000-the cost of
the insurance deductable."
mike regish
"Dan Youngquist" <gringo...@yahoo.com> wrote in message
news:Pine.NEB.4.61.05...@otaku.freeshell.org...
Cub Driver
<mre...@comcast.net> wrote:
>"Wrong. The most expensive plane you'll ever fly is about $1000-the cost of
>the insurance deductable."
Well, that's a view, but it's not a very good one in my opinion. If
you pay a million dollars for an airplane, it costs a whole lot more
than the insurance deductible: for one thing, you must pay the
"opportunity cost" that that million dollars would have earned for
you, say $50,000 a year if it were invested in a stock index fund over
the years and returned a mere 5 percent in dividends and appreciation.
It's also bad economics to think that passing a cost to the insurance
company is getting rid of it altogether: you're in fact passing it to
all the people who carry insurance.
-- all the best, Dan Ford
email war...@mailblocks.com (put Cubdriver in subject line)
Warbird's Forum: www.warbirdforum.com
Piper Cub Forum: www.pipercubforum.com
the blog: www.danford.net
Jose
>> the insurance deductable."
>
>
>
> It's also bad economics to think that passing a cost to the insurance
> company is getting rid of it altogether: you're in fact passing it to
> all the people who carry insurance.
I think the point was that the time to think about the plane only being
worth the deductable is when you have an emergency and have to decide
between risking the plane to save the people, and risking the people to
save a one million dollar plane. At that point, think of it as a one
thousand dollar plane.
Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.
mike regish
save the plane. Keep the props turning and let the insurance pay for the
teardown rather than medical and funeral expenses.
mike regish
"Cub Driver" <war...@mailblocks.com> wrote in message
news:n71h111naii7l3u3u...@4ax.com...
Cub Driver
wrote:
>I think the point was that the time to think about the plane only being
>worth the deductable is when you have an emergency and have to decide
>between risking the plane to save the people, and risking the people to
>save a one million dollar plane. At that point, think of it as a one
>thousand dollar plane.
Oh, good point. Yes, I would try to think of it like a $20 digital
watch: if the battery gives out, throw it away and buy another!
nf...@home.com
> watch: if the battery gives out, throw it away and buy another!
Not long ago I bought a digital watch at Dollar Tree. One guess as to
what it cost. Worked fine for about a month, at which time the battery
gave out. But at that price, who cares? Just buy another one.
I also bought a scientific calculator at Dollar Tree awhile back.
The same logic applies. Amazing, considering what one would have
paid for these items 20 years ago.
David Johnson