thrust tube collapse
03-31-2009 | 01:50 PM
#1
Thread Starter
My Feedback: (30)
thrust tube collapse
Hello,
I had a collapse thrust tube on my second flight of my avonds F-16. This is the third time thrust tube has collapsed, twice with the previous owner and one more time yesterday. I feel there is something wrong which i want to share with you:
First of all the diameter of inner thrust tube is 67 mm where as the outer cone of P80 is 63mm. This leaves the margin of 2mm in radius or shall I say 2mm all around.
Currenly I am using carbon/Kevlar bypass, as original bypass burnt first time tail pipe deformed with the previous owner. This and BVM heat shield might have saved my aircraft from excessive heat.
The distance between exhaust cone of P80 and start of inner thrust tube (this is a double walled thrust tube with bypass) is 10mm.
Could someone let me know what could be wrong here.
I am also using FOD screen, and someone told me that FOD screen create uneven pressure inside bypass system and could have caused collapse.
Is it better to get rid of bypass system and get a new pipe with bell mouth?....something like Tamjets pipe?
Please giev me your input.
Best Regards
Asif
I had a collapse thrust tube on my second flight of my avonds F-16. This is the third time thrust tube has collapsed, twice with the previous owner and one more time yesterday. I feel there is something wrong which i want to share with you:
First of all the diameter of inner thrust tube is 67 mm where as the outer cone of P80 is 63mm. This leaves the margin of 2mm in radius or shall I say 2mm all around.
Currenly I am using carbon/Kevlar bypass, as original bypass burnt first time tail pipe deformed with the previous owner. This and BVM heat shield might have saved my aircraft from excessive heat.
The distance between exhaust cone of P80 and start of inner thrust tube (this is a double walled thrust tube with bypass) is 10mm.
Could someone let me know what could be wrong here.
I am also using FOD screen, and someone told me that FOD screen create uneven pressure inside bypass system and could have caused collapse.
Is it better to get rid of bypass system and get a new pipe with bell mouth?....something like Tamjets pipe?
Please giev me your input.
Best Regards
Asif
03-31-2009 | 03:19 PM
#2
My Feedback: (10)
RE: thrust tube collapse
Hello Asif,
Sorry about your plane. Unfortunately, I don't know anything about that plane, but were you able to make sure the P-80 is starting without excessive flames (I mean big hot flames). Sometimes in an internal install you never see them. This can weaken the pipe and cause a collapse.
Are you using the stock Avonds supplied bypass and tailpipe? If so, what does Avonds say about the fit of the P-80 in the bypass?
Sorry about your plane. Unfortunately, I don't know anything about that plane, but were you able to make sure the P-80 is starting without excessive flames (I mean big hot flames). Sometimes in an internal install you never see them. This can weaken the pipe and cause a collapse.
Are you using the stock Avonds supplied bypass and tailpipe? If so, what does Avonds say about the fit of the P-80 in the bypass?
04-01-2009 | 01:24 AM
#4
Thread Starter
My Feedback: (30)
RE: thrust tube collapse
Matt,
I am using stock avonds pipe and setup...... I did realize that inlet sound had changed and I was not getting enough thrust, so I landed, and notice collapse pipe. There is not damage to anything.. I contacted philip avonds, he has helped me with all the question I had.
Intrestingly, Ali Machinchi told me I had collapse pipe because the FOD screen that I use creates uneven airflow and that caused collapse pipe. It has happened to him twice in his bandit, so the solution was to get rid of FOD screen when using a bypass system.
Regards
Asif
I am using stock avonds pipe and setup...... I did realize that inlet sound had changed and I was not getting enough thrust, so I landed, and notice collapse pipe. There is not damage to anything.. I contacted philip avonds, he has helped me with all the question I had.
Intrestingly, Ali Machinchi told me I had collapse pipe because the FOD screen that I use creates uneven airflow and that caused collapse pipe. It has happened to him twice in his bandit, so the solution was to get rid of FOD screen when using a bypass system.
Regards
Asif
04-01-2009 | 01:31 AM
#5
Thread Starter
My Feedback: (30)
RE: thrust tube collapse
KC36330,
The pipe was sort of flexible even before the collapse.....the problem I feel was that inner pipe was not 100% secure and has movement of about 2mm...... there was no room for this movement as total clearance is 2mm all around.
Regards
Asif
The pipe was sort of flexible even before the collapse.....the problem I feel was that inner pipe was not 100% secure and has movement of about 2mm...... there was no room for this movement as total clearance is 2mm all around.
Regards
Asif
