Thu Jan 01, 2009 10:09 am
Here's a picture of a 1340 cylinder that had a bit of a mishap with me while I was taking off in a T-6. I may fill in the rest of the story later...not in much of a writing mood right now. 
Gary
Gary
Thu Jan 01, 2009 10:50 am
(May I step in........)
Quote by IndyJen:
Interestingly--to me at least--is that both times, the engine seemingly ran the smoothest and best ever right beforehand.
-Likewise. My 2 massive Merlin failures, the engines were turbine smooth. Now I don't like turbine smooth Merlins.
VL
Quote by IndyJen:
Interestingly--to me at least--is that both times, the engine seemingly ran the smoothest and best ever right beforehand.
-Likewise. My 2 massive Merlin failures, the engines were turbine smooth. Now I don't like turbine smooth Merlins.
VL
Thu Jan 01, 2009 2:19 pm
On a Catalina I used to fly in we had the right hand engine blow an induction pipe about 10 minutes after we got airborne. The pipe blew through one of the cowl flaps and hit the right hand side of the horizontal stab. A fire started. That was exciting. We had already made our way back to the airport and was on a base leg when it blew. We landed and rolled off the runway. The story is a bit longer but what is interesting is that there had been one of the Turbine S2's flying behind us. The pilot had been called to a fire near Sonoma Mountain in Sonoma County and then was called off. This pilot later told me at the bar that he saw the engine torch off. He also said that if he thought the fire might get out of control while we were rolling out he would have been tempted to drop a load on us. I said, "You mean like in the movie "Always"? He laughed and said, "Yeah!" The engine had about 30 hours on it since overhaul. The previous engine had about 25 hours on it when it started to pack it up. It had chrome cylinders. Three of those cylinders had chrome rings on the pistons. Not a good combination. All in all the old Pratt & Whitney engine kept making power. A friend of mine the late, Airport Bob from the old navy base south of town was driving around the west side of the airport and saw us on fire. He took these photos from a camera over his shoulder of us on short final.
Jim Long
http://s152.photobucket.com/albums/s184 ... =21CFR.jpg
http://s152.photobucket.com/albums/s184 ... 21CFR2.jpg
Jim Long
http://s152.photobucket.com/albums/s184 ... =21CFR.jpg
http://s152.photobucket.com/albums/s184 ... 21CFR2.jpg
Thu Jan 01, 2009 2:50 pm
(A26) 2800 piston:
other side:
& yes, of course it's clean! Not going to put it on the mantel cover in oil
other side:
& yes, of course it's clean! Not going to put it on the mantel cover in oil
Last edited by ZRX61 on Thu Jan 01, 2009 2:57 pm, edited 2 times in total.
Thu Jan 01, 2009 2:54 pm
Spot the (F7F) valve seat....
Thu Jan 01, 2009 7:24 pm
IndyJen wrote:I've had a couple R-2800's fail. Both times it was a bad main bearing. The failure mode there consistently was engine lockup on shutdown.
Interestingly--to me at least--is that both times, the engine seemingly ran the smoothest and best ever right beforehand. Then you shut 'er down, and she stops normally. Come back a while later, and she's locked up and immobile.
The first time this happened, we'd just checked the oil screens a couple hours previously, and that engine was clean and good. Pulled the screen after the lockup, and it was choked with metal, to the point where it was a bit difficult to get the screen out of the cavity.
The last time this happened, we were doing ground runs. Shut down normally and went to start up again, and ... clank. That starter's in the shop now, because an inertial starter doesn't like it when you engage and the engine doesn't turn at all.
Mains? Not master rod? Was it B series?
Thu Jan 01, 2009 7:52 pm
Not a recip but I had this turboprop grenade on me. T-56A-15 #4 Engine. Nice little fire light. We got it out with the first bottle and of course the WX was at mins at KDYS. Ah, the Herk flys just fine on 3 engines.
That is the CC in the first picture.
Instide #4 engine looking outboard.
That is the bleedair lines in the upper drybay.
Flying is fun, flying is fun, flying is fun.
Kel
That is the CC in the first picture.
Instide #4 engine looking outboard.
That is the bleedair lines in the upper drybay.
Flying is fun, flying is fun, flying is fun.
Kel
Thu Jan 01, 2009 7:53 pm
Gary, I have a 1340 jug here that looks just like that.
Carl had a student in the front seat and they had just taken off and were about to retract the gear when the engine went BANG and shook like mad. Carl took over and landed back on the runway. When he got back the hangar, the plane was running fine, until you got to 30 inches, then it would backfire with white smoke. We checked fuel screens and looked the engine over and could not see anything amiss. I decieded to remove the cowl and perform a compression check, when I put the spark plug socket on #3 and gave a tug, then head lifted off the cylinder, it was only held in place by the drain tubes, baffles, and pushrod tubes. Carl had run of somewhere and when he returned I all ready had the exhaust off, baffles free. He asked what I was doing and I pulled the head off the cylinder and handed it to him and said, Any more questions ?
Carl had a student in the front seat and they had just taken off and were about to retract the gear when the engine went BANG and shook like mad. Carl took over and landed back on the runway. When he got back the hangar, the plane was running fine, until you got to 30 inches, then it would backfire with white smoke. We checked fuel screens and looked the engine over and could not see anything amiss. I decieded to remove the cowl and perform a compression check, when I put the spark plug socket on #3 and gave a tug, then head lifted off the cylinder, it was only held in place by the drain tubes, baffles, and pushrod tubes. Carl had run of somewhere and when he returned I all ready had the exhaust off, baffles free. He asked what I was doing and I pulled the head off the cylinder and handed it to him and said, Any more questions ?
Fri Jan 02, 2009 12:10 am
One of the Aleutian PBY veterans on PBY@yahoogroups told of an 1830 on a Cat that broke a piston rod on a bottom jug and kept on flying without incident. Flying for some time. No one noticed anything wrong and they only found it when it was down for some major maint. Said it fly like any war weary Pratt. Get to know your airplane and work within its limits and keep going.
Fri Jan 02, 2009 1:39 am
Yeah T-56A belongs in its own thread, titled turbine da boom boom.
Its pretty much a given that a turbine will do that since they do rev so high a slight imbalance would make them go wacko.
Personally I can't understand how they get the hours they do out of them.
Some pretty high stresses on parts, centrifugal and heat. One little crack and a blade or two breaks off then total destruction. And ya think it would be a big expense to overhaul a big radial like a wasp major, thats nothin compaired to a big jet engine. I bet its in the millions range to overhaul a jet.
Its pretty much a given that a turbine will do that since they do rev so high a slight imbalance would make them go wacko.
Personally I can't understand how they get the hours they do out of them.
Some pretty high stresses on parts, centrifugal and heat. One little crack and a blade or two breaks off then total destruction. And ya think it would be a big expense to overhaul a big radial like a wasp major, thats nothin compaired to a big jet engine. I bet its in the millions range to overhaul a jet.
Fri Jan 02, 2009 10:57 am
Engguy sez:
Well, that is a question, at that. It is a B series engine, a dash 31. The overhauler reported bearing bad, and as part of our rebuild, we did get both a new master rod and a new crankcase, so apparently everything associated with that bearing took a beating. Still, the shop names the bearing as the culprit, so that's why I phrased it like I did.
The other engine, I guess we don't know for exact sure what all is up with it. Locked up on shutdown, it did, and put a whole lot of metal in the screen, much of it ferrous. Could be some master rod in that, but we suspect a bad bearing there, too--much less metal, and hardly any ferrous--and it could also be a failure in the accessory drive: that's what George the AI thinks. We won't know for sure until we tear it down some, and can look at it. There's no money to do anything with that engine right now, and being generally short-handed anyhow, we haven't really looked at it.
We have learned some lessons the hard way with this. One of those things is that operating by the ww2 book can do bad things to you, sometimes. Another thing is that pre-oiling is not only a good thing, it is something you just gotta do, period.
Mains? Not master rod? Was it B series?
Well, that is a question, at that. It is a B series engine, a dash 31. The overhauler reported bearing bad, and as part of our rebuild, we did get both a new master rod and a new crankcase, so apparently everything associated with that bearing took a beating. Still, the shop names the bearing as the culprit, so that's why I phrased it like I did.
The other engine, I guess we don't know for exact sure what all is up with it. Locked up on shutdown, it did, and put a whole lot of metal in the screen, much of it ferrous. Could be some master rod in that, but we suspect a bad bearing there, too--much less metal, and hardly any ferrous--and it could also be a failure in the accessory drive: that's what George the AI thinks. We won't know for sure until we tear it down some, and can look at it. There's no money to do anything with that engine right now, and being generally short-handed anyhow, we haven't really looked at it.
We have learned some lessons the hard way with this. One of those things is that operating by the ww2 book can do bad things to you, sometimes. Another thing is that pre-oiling is not only a good thing, it is something you just gotta do, period.
Fri Jan 02, 2009 11:02 am
Ah drat it. When I say
above, I am referring to the engine we just got rebuilt. Too much editing, and not enough proofreading. The still-locked-up boat-anchor engine had metal galore. The one we got rebuilt didn't have nearly as much, and that was why we elected to send it instead of the other. It still had plenty of Bad Things inside it. Lord knows what the remaining engine will look like when it's opened up.
--much less metal, and hardly any ferrous--
above, I am referring to the engine we just got rebuilt. Too much editing, and not enough proofreading. The still-locked-up boat-anchor engine had metal galore. The one we got rebuilt didn't have nearly as much, and that was why we elected to send it instead of the other. It still had plenty of Bad Things inside it. Lord knows what the remaining engine will look like when it's opened up.
Fri Jan 02, 2009 3:41 pm
The B's have a different crank than the newer ones, and can see why they could have problems.
Fri Jan 02, 2009 3:41 pm
I read an autobiography by an early Pan Am pilot. He started in the 1930s when you couldn't get a copilot slot until after you had earned your A&E license on the hangar floor. On one trip in an early Consolidated flying boat they lost cylinder for some reason. Standard practice was to remove the push rods and the spark plugs in the bad cylinder and ferry home with 8 cylinders working.
Fri Jan 02, 2009 4:48 pm
N3Njeff wrote:Looks fake to me.........................and to answer the question.............Yes twice!
The engine failed in flight over northern AZ. The cylinder that is there now is not the one that failed. That one is laying in the desert someplace up near the Grand Canyon. They made an emergency landing immediately after the failure. We took an engine off one of our other planes, and got a new cowl off another 404 and replaced the damaged parts to finish the flight down. Once it arrived the good engine went back on the plane it came from and they put the damaged parts back on the 404 and stuck an extra cylinder in the hole to show people what had happened. We plan to put the replacement cowl back on when we get around to repainting the airplane.
James