R
Roger, Roger
Guest
Hmm...177? 210? I know our mechs use the one on 172 all the time. I trust their judgment that it won't break anything.
Tailstrike question?
- Thread starter popaviator
- Start date
granlistillo
Well-Known Member
There was a service bulletin on one model calling for inspections I believe. I have heard it in more than one place. I used to be a mech, and build planes in a former life, but that was about 20 years ago. I still though am not totally ignorant on the subject. It is a poor practice. Either heed it or not...
Did a quick search and got this off AOPA site on doing preflights.
http://flighttraining.aopa.org/ft_magazine/fullstory.cfm?id=518&issue_title=July+1994
TAIL ASSEMBLY - 3
Make sure any exterior gust locks are removed from the tail and check the control cables and connectors to ensure everything is secure and not worn or frayed. Check the elevator and horizontal stabilizer/stabilator surfaces for damage. Dented or bowed surfaces are often not just skin deep; they may be an indication of structural problems. Tail sections on Cessnas are particularly susceptible to structural damage caused by those who push down on them to raise the nose while repositioning the aircraft.
Don't forget to check the bottom of the horizontal surfaces; serious damage may be more likely to occur there. This area is prone to damage from rocks kicked up by the tires or from a tail strike during a botched landing. Also inspect the outer edges of the elevator or stabilator, and the tail tiedown, as they can also be damaged from a tail-low landing.
When inspecting a Cessna 152 damaged in a tail-low crosswind landing, the only evidence of damage on the top of the horizontal stabilizer was a slight inward bowing of the skin - a condition that perhaps a dozen pilots attributed to mere cosmetic damage. The aircraft flew for three weeks in this condition and nobody suspected a problem. Then a particularly observant student questioned the indentation and checked underneath the stabilizer, where he found major scrape marks on the bottom of the stabilizer tip. The bowing of the skin was due to a bent spar. The aircraft was unairworthy and the stabilizer had to be replaced.
On aircraft equipped with stabilators rather than horizontal stabilizers and elevators, grasp the stabilator on the outboard edge and check for any play in the hinge assembly. Excess play can lead to flutter and subsequent catastrophic failure of the control surface. Don't forget the trim tab. In one case, a cracked trim tab on a Cherokee required full nose down trim to keep the aircraft in level flight. Make sure it is securely attached and free of any cracks.
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then there is from apparently very experienced mechanic.
http://www.littleflyers.com/Questions/cessna/172issues.htm
Problems and issues with a high time Cessna 172
Sent: Sunday, February 15, 2004 12:28 PM
Subject: High Time Cessna 172
Roger,
What are the issues in buying a high time 1973 Cessna 172; total hours 9100?
Thanks,
P.A.
<HR>Subject: High Time Cessna 172
Roger,
What are the issues in buying a high time 1973 Cessna 172; total hours 9100?
Thanks,
P.A.
Roger's reply,
The Cessna 172 is a good aircraft. However, high time aircraft tend to have issues. For the year you specify gear leg fatigue can occur, and the fatigue will cause the tires to wear very prematurely. The main gear support structure can crack or buckle. There is a high probability of firewall damage at the nose gear strut attach. Fuel tanks can be fatigued from the expansion and contraction of the fuel tank. Flap tracks can be excessively worn from very repetitive usage. The flap arms may be worn if the improved wear washers were not installed. Fatigue and cracking of flap skins may occur from the number of powered stalls performed. The horizontal stabilizer may be damaged from ground handling from pushing down on the tail. Finally, expect issues with baffles, exhaust, and the propeller. Roger
The Cessna 172 is a good aircraft. However, high time aircraft tend to have issues. For the year you specify gear leg fatigue can occur, and the fatigue will cause the tires to wear very prematurely. The main gear support structure can crack or buckle. There is a high probability of firewall damage at the nose gear strut attach. Fuel tanks can be fatigued from the expansion and contraction of the fuel tank. Flap tracks can be excessively worn from very repetitive usage. The flap arms may be worn if the improved wear washers were not installed. Fatigue and cracking of flap skins may occur from the number of powered stalls performed. The horizontal stabilizer may be damaged from ground handling from pushing down on the tail. Finally, expect issues with baffles, exhaust, and the propeller. Roger
Yup I'm with you. Our mechanic was cool with the procedure as any work it caused was less than that of a tail strike. Also consider that the tail surface produces "down" lift. The horizontal stab is in inverted wing. We also have an STC to replace the part where the tiedown ring attaches (anybody remember what that's called?) with the identical part from a 210. The part is identical in all respects except a bit thicker.
Our management decided that they would do a few things to make our life easier in terms of tailstikes after a rash of them.
LC
R
Roger, Roger
Guest
My understanding is that most damage to the tail caused by moving the airplane is from people pushing on the skin, not on the spar.
tgrayson
New Member
It does, but also consider that the force is distributed all over the surface of the horizontal stabilizer, rather than at one particular point, which is what's occurring when you push with your hand. I make sure that I apply most of my force to the tailcone, rather than the horizontal surface.
granlistillo
Well-Known Member
I am familiar with the purpose of the horizontal stab.
The airloads placed more or less evenly across the entire horizontal surfaces to control pitch around the CG during flight are much much less than the load you are putting on the stab by pushing down on your hands and rotating it around the wheels. Not even close. When you push on the edge and not right on top of the spar, you are putting a torsion load on it you will never ever get in flight and it was never designed or tested to bear.
The manufacturer has come out and said don't do it, it wasn't designed for it. Not all stress is apparent and visible to the eye. BTW, There are mechanics out there that are incompetent just like pilots.
If you guys are going to do it, I would research it a little better.
granlistillo
Well-Known Member
uh no, the spar. Also skin wrinkling is usually and indication of damage deeper in the structure. Beauty is not in this case skin deep.
In your succint response, you beat me to the punch.
If I absolutely had to do it, I would tie a knot in the tail tie down rope. Run the rope through the tie down eyelet and pull the tail down. This would allow for the student to see the sight picture. And it wouldnt hurt the airplane.
cj4pilot
Well-Known Member
Do not maneuver airplanes on the ground by pushing down on the tail. Buy a tow bar, or don't be lazy, or don't try to look so cool. If Cessna wanted you to be able to steer that way on the ground, a Tow bar wouldn't come with the airplane. Not to mention how many people flat spot the nose tire because it's not fully off the ground when they do their macho 172 ground handling procedure. Wow, you look cool because you can manhandle this airplane, and really show it who's boss.
SpiceWeasel
Tre Kronor
About the ground handling.... I've seen mechanics use the "macho" procedure.....
Re: tailstrike.... it happens..... We have a CRJ-900 that had a tail strike a month or 2 ago. Holy crap!
trafficinsight
Well-Known Member
Blast from the paaaaaast.
If there's no damage to the skin around the mount just order the tiedown ring and screw it in there. But if there's any damage or the tiedown ring won't screw in or when it does screw in it's loose you're going to have to get a mechanic to repair it.
Sent from my Moto Z (2) using Tapatalk
trafficinsight
Well-Known Member
killbilly
Vocals, Lyrics, Triangle, Washboard, Kittens
I had the same thought. Bit of nostalgia seeing a post from Ben Hill, and also seeing @Roger Roger posting from a guest account.
D
Deleted member 27505
Guest
Well, yeah. Plus... it's obvious we didn't solve the problem on our first pass, eh?
Roger Roger
Bottom of the list
I had the same thought. Bit of nostalgia seeing a post from Ben Hill, and also seeing @Roger Roger posting from a guest account.
FloridaLarry
Well-Known Member
1. Buy a plane ticket to Vegas.
2. Pack your inhibitions and your good sense in your suitcase. Make sure the gate agent tags it to the wrong destination. Consume alcohol during the flight.
3. Check into the sleasiest motel you can find in Vegas.
4. Cross your fingers and have a drink. Repeat. Repeat again. And...
5. Do not plan on dating anyone whose phone number you found on a streetlight pole.
6. After returning home (presuming you can find it, and your significant other hasn't changed the locks), visit your AME for a course of penicillin.
Good luck.
🦈💜
Well-Known Member
And while you’re at it, make a bunch of women “walk the gauntlet” while sexually assaulting them...