Scuffed It To A Nub

[Eric]

Tail strike in Guadalajara last Friday.

 

[Eric]

Mother Nature has no respect for CG.

 

[jmohme]

Ouch!

[railfancwb]

Remember getting on a red eye Southwestern flight, almost all seats empty. The staff seated passengers to deal with left/right front/rear CG as well as possible. 

[Eric]

This was a nearly perfect landing. Nearly.

 

[Eric]

[Eric]

[Eric]

This guy just missed going for a hell of a ride.

 

[Eric]

Feeding time.

 

[jmohme]

10 minutes ago, Eric said:

This guy just missed going for a hell of a ride.

 

[jmohme]

19 minutes ago, Eric said:

This was a nearly perfect landing. Nearly.

 

Oh, That thing on top is a skid, not a wing. Now I get the whole biplane thing.

 

[Eric]

29 minutes ago, railfancwb said:

Remember getting on a red eye Southwestern flight, almost all seats empty. The staff seated passengers to deal with left/right front/rear CG as well as possible. 

If all the passengers on a crowded airliner were to get up and move forward or aft and pack themselves into a tight group there, I wonder if the CG shift would be enough to make the aircraft unflyable?

[GT4494]

1 minute ago, Eric said:

If all the passengers on a crowded airliner were to get up and move forward or aft and pack themselves into a tight group there, I wonder if the CG shift would be enough to make the aircraft unflyable?

Yes.  Just think of what happens when a tractor trailer load shifts.  Except, what goes up must come down!!!

[Eric]

2 hours ago, GT4494 said:

Yes.  Just think of what happens when a tractor trailer load shifts.  Except, what goes up must come down!!!

One thing that would mitigate the passengers' affect on CG would be their volume relative to their mass. Even tightly packed, the mass of passengers would still cover quite a distance towards the aircraft's center of gravity, reducing their impact on the imbalance being caused. Plus, the aircraft has trim tabs to compensate for load imbalances, to a point. When large aircraft have crashed due to CG problems, it has usually been because something heavy and dense shifted or was loaded improperly. The cargo aircraft that crashed in Iraq probably went down because an MWrap vehicle broke free and shifted aft during climbout. It only shifted ten feet or so, but it was enough for an already tail-heavy aircraft to become impossible to control. An MWrap weighs something like 16 tons. How large a volume of people would it take to equal that weight? I'm guessing 200 people or more. That many people take up a lot of space. Could enough people shift far enough to have a critical effect on CG?

[jmohme]

5 minutes ago, Eric said:

If all the passengers on a crowded airliner were to get up and move forward or aft and pack themselves into a tight group there, I wonder if the CG shift would be enough to make the aircraft unflyable?

Apples and Oranges I know, but back in the 70s, I was working at a Standard gas station. Kenny, the owner and I were outside and heard a noise, looked up and saw an ultralight flying over and heading for the little grass field airport where Kenny kept is Cesna, so since we had nothing in the shop bays we left the station to the gas jockey kid and headed down there. 

The guy had landed and was more than happy to tell us everything about it. He was flying this home built thing cross country and landed at this field waiting for his pit crew that was following in a pickup. The little ultra light had no controls other than throttle. Everything else was done by the pilot leaning forward, backward, left, or right. Sounded pretty iffy to me.

Kenny and I headed back to the gas station, and some time later we saw the little plane flying and doint fancy little maneuvers, including a steep climb folowed by an uncontroled tumble to do the ground. Kenny and I headed back there when we saw the ambulance head down the hill.

Fortunately the trees slowed his fall and he ended up landing butt first in the creek surround by what was left of the ultralight. It turns out he had is harness too tight and could not lean far enough forward to pull out of the climb, stalled and could not recover. OOPS.

CG problems can be a bitch!

[Eric]

1 minute ago, jmohme said:

Apples and Oranges I know, but back in the 70s, I was working at a Standard gas station. Kenny, the owner and I were outside and heard a noise, looked up and saw an ultralight flying over and heading for the little grass field airport where Kenny kept is Cesna, so since we had nothing in the shop bays we left the station to the gas jockey kid and headed down there. 

The guy had landed and was more than happy to tell us everything about it. He was flying this home built thing cross country and landed at this field waiting for his pit crew that was following in a pickup. The little ultra light had no controls other than throttle. Everything else was done by the pilot leaning forward, backward, left, or right. Sounded pretty iffy to me.

Kenny and I headed back to the gas station, and some time later we saw the little plane flying and doint fancy little maneuvers, including a steep climb folowed by an uncontroled tumble to do the ground. Kenny and I headed back there when we saw the ambulance head down the hill.

Fortunately the trees slowed his fall and he ended up landing butt first in the creek surround by what was left of the ultralight. It turns out he had is harness too tight and could not lean far enough forward to pull out of the climb, stalled and could not recover. OOPS.

CG problems can be a bitch!

It's hard to make anything idiot-proof because idiots are so resourceful.

[jmohme]

Just now, jmohme said:

Apples and Oranges I know, but back in the 70s, I was working at a Standard gas station. Kenny, the owner and I were outside and heard a noise, looked up and saw an ultralight flying over and heading for the little grass field airport where Kenny kept is Cesna, so since we had nothing in the shop bays we left the station to the gas jockey kid and headed down there. 

The guy had landed and was more than happy to tell us everything about it. He was flying this home built thing cross country and landed at this field waiting for his pit crew that was following in a pickup. The little ultra light had no controls other than throttle. Everything else was done by the pilot leaning forward, backward, left, or right. Sounded pretty iffy to me.

Kenny and I headed back to the gas station, and some time later we saw the little plane flying and doint fancy little maneuvers, including a steep climb folowed by an uncontroled tumble to do the ground. Kenny and I headed back there when we saw the ambulance head down the hill.

Fortunately the trees slowed his fall and he ended up landing butt first in the creek surround by what was left of the ultralight. It turns out he had is harness too tight and could not lean far enough forward to pull out of the climb, stalled and could not recover. OOPS.

CG problems can be a bitch!

Also, it turns out that this guy was active Air Force.

He only thought his ass hurt after landing in the creek. It seems that the Airforce frowns on its people playing with unsafe flying toys when they have the real thing to work with when they have responsibilities relating to the real deal.

[jmohme]

1 minute ago, Eric said:

It's hard to make anything idiot-proof because idiots are so resourceful.

I was always told that if you manage to make it idiot proof, somone will just make a better idiot.

I have seen that proven true far to many times.

[Eric]

Just now, jmohme said:

I was always told that if you manage to make it idiot proof, somone will just make a better idiot.

I have seen that proven true far to many times.

Truer words were never spoken.

[Eric]

6 minutes ago, jmohme said:

Also, it turns out that this guy was active Air Force.

He only thought his ass hurt after landing in the creek. It seems that the Airforce frowns on its people playing with unsafe flying toys when they have the real thing to work with when they have responsibilities relating to the real deal.

When I was in the Army, they told us quite clearly that anything stupid we did, on our own time or not, that made us unfit for duty would be punished. I saw that happen a couple of times. When you are in, they own your ass and they don't appreciate people damaging their property. I knew a guy that took battery powered hunting socks with him on a very cold field problem. The problem arose because the dumbass didn't bring replacement batteries. Warm feet sweat and cold, wet feet freeze. He ended up with frostbite in three toes and lost the littlest piggy. He received a Company Grade Article 15 for it. It cost him a stripe, two weeks pay and two weeks restriction & extra duty.

[DAKA]

Friend of mine fell down some stairs coming out of a "BAR"   (wink. wink, nod, nod)  while at a post, broke his arm, we carried him screaming back to the post and put him at the bottom of stairs, 

needless to say it was suspicious, but the sergeant did not want to go through the rigamarole of reports and just reported it as a fall     pure luck on all counts......Valuable lesson learned

WHILE OFF POST BE CAREFUL COMING OUT OF "BARS"  

[GT4494]

3 hours ago, Eric said:

One thing that would mitigate the passengers' affect on CG would be their volume relative to their mass. Even tightly packed, the mass of passengers would still cover quite a distance towards the aircraft's center of gravity, reducing their impact on the imbalance being caused. Plus, the aircraft has trim tabs to compensate for load imbalances, to a point. When large aircraft have crashed due to CG problems, it has usually been because something heavy and dense shifted or was loaded improperly. The cargo aircraft that crashed in Iraq probably went down because an MWrap vehicle broke free and shifted aft during climbout. It only shifted ten feet or so, but it was enough for an already tail-heavy aircraft to become impossible to control. An MWrap weighs something like 16 tons. How large a volume of people would it take to equal that weight? I'm guessing 200 people or more. That many people take up a lot of space. Could enough people shift far enough to have a critical effect on CG?

It all depends on the size of the aircraft.  A lot of people can move around in a 747 and not bother the CG.  On the other hand a heavy piece of luggage can crash a small Cessna.  There is an interesting formula for figuring the CG on a smaller aircraft. It includes weights (people and luggage), distance from CG (both ways).  Then you use the weight info and temp/humidity to calculate runway length needed and rate of climb.   

Like a lot other things in life, its the little mistakes that will kill you every time. 

[Eric]

10 minutes ago, GT4494 said:

It all depends on the size of the aircraft.  A lot of people can move around in a 747 and not bother the CG.  On the other hand a heavy piece of luggage can crash a small Cessna.  There is an interesting formula for figuring the CG on a smaller aircraft. It includes weights (people and luggage), distance from CG (both ways).  Then you use the weight info and temp/humidity to calculate runway length needed and rate of climb.   

Like a lot other things in life, its the little mistakes that will kill you every time. 

Yep, or how small things can roll other circumstances into big things. I watched an Air Disaster episode years ago where a cargo aircraft miscalculated their CG, so they didn't have the correct trim setting on takeoff. They were tail-heavy, but still within the flight envelope of the aircraft. It was a complication though that bit them in the ass at a critical time in the flight. As the aircraft took off it was obviously nose up, as the pilots expected it to be,  and it took the pilots a few precious seconds to realize that the rate of climb kept increasing. By the time they realized it, they were pitched way too high, only a few hundred feet from the ground. It would have been a recoverable problem with more speed or more altitude, but they had neither and no time. They stalled and crashed, killing the flight crew and completely destroying the aircraft.

[DAKA]

35 minutes ago, GT4494 said:

It all depends on the size of the aircraft.  A lot of people can move around in a 747 and not bother the CG.  On the other hand a heavy piece of luggage can crash a small Cessna.  There is an interesting formula for figuring the CG on a smaller aircraft. It includes weights (people and luggage), distance from CG (both ways).  Then you use the weight info and temp/humidity to calculate runway length needed and rate of climb.   

Like a lot other things in life, its the little mistakes that will kill you every time. 

Sometimes You get lucky and it's just an "underwear" problem 

[geeorge]

5 hours ago, Eric said:

Mother Nature has no respect for CG.

 

looks like a penquin