New kid in town...
Mon Oct 09, 2006 8:54 pm
Hi!
My name is Russ and I have just joined the forum. I am a retired USAF Master Sergeant, having worked in the Aircraft Maintenance field. I was a Crew Chief on T-33's and B-1B's, and later a Maintenence Supervisor on B-1's.
I found out about this forum from Shay Geeding who started the thread about T-33 58-0510, which was my aircraft at Griffiss AFB. It was really great to hear from him with his pictures.
If anyone has any questions that I could answer about T-33's or B-1's or the Air Force in general, I would be glad to try to answer them.
Good to be here!
Russ
My name is Russ and I have just joined the forum. I am a retired USAF Master Sergeant, having worked in the Aircraft Maintenance field. I was a Crew Chief on T-33's and B-1B's, and later a Maintenence Supervisor on B-1's.
I found out about this forum from Shay Geeding who started the thread about T-33 58-0510, which was my aircraft at Griffiss AFB. It was really great to hear from him with his pictures.
If anyone has any questions that I could answer about T-33's or B-1's or the Air Force in general, I would be glad to try to answer them.
Good to be here!
Russ
Mon Oct 09, 2006 9:04 pm
Welcome to the board Russ, I have a T-33 question. What or why would a T-33 not be able to get fuel from the wing tip tanks. There is one at our airport that has this problem. I never really asked any tech questions about it, but was told that they couldn't get the tanks to pressurize and couldn't get it to work for them I think.
Thanks for your time,
Lynn
Thanks for your time,
Lynn
???
Mon Oct 09, 2006 9:05 pm
Welcome aboard Russ,
When we took the B-25 to NAS Whidbey a couple years ago I traded T-shirts and tours with a B-1 crew. What a cool machine! It amazes me with such a huge bird how little room there is for the crew.
When we took the B-25 to NAS Whidbey a couple years ago I traded T-shirts and tours with a B-1 crew. What a cool machine! It amazes me with such a huge bird how little room there is for the crew.
Mon Oct 09, 2006 9:49 pm
Thanks for the welcome!
Lynn Allen: The T-33 has to transfer fuel from the various tanks to the fuselage tank, which is the only one that feeds the engine. The wing tanks all had pumps for this purpose, but the tip tanks depended on pressurization from the engine bleed air system to transfer. The problem probably lay in the valves that control the air, or possibly a leaking sniffle valve, a check valve that alowed atmospheric pressure into the tank under certain circumstances but sealed to allow the tanks to pressurize. If one was not seating properly, the the tank couldn't pressurize. These would sometimes leak fuel on the ground and we would have to pull the wing fairing panel off the inboard side of the tank and stick a finger in the valve to seat it properly. High tech stuff, huh?
Jack Cook: Yeah, the cockpit area of the B-1 is pretty small. I went through the Collings Foundation B-17 )Nine-o-nine) a few weeks ago and the flight deck of that aircraft really wasn't that much smaller than the B-1's.
Russ
Lynn Allen: The T-33 has to transfer fuel from the various tanks to the fuselage tank, which is the only one that feeds the engine. The wing tanks all had pumps for this purpose, but the tip tanks depended on pressurization from the engine bleed air system to transfer. The problem probably lay in the valves that control the air, or possibly a leaking sniffle valve, a check valve that alowed atmospheric pressure into the tank under certain circumstances but sealed to allow the tanks to pressurize. If one was not seating properly, the the tank couldn't pressurize. These would sometimes leak fuel on the ground and we would have to pull the wing fairing panel off the inboard side of the tank and stick a finger in the valve to seat it properly. High tech stuff, huh?
Jack Cook: Yeah, the cockpit area of the B-1 is pretty small. I went through the Collings Foundation B-17 )Nine-o-nine) a few weeks ago and the flight deck of that aircraft really wasn't that much smaller than the B-1's.
Russ
Mon Oct 09, 2006 10:09 pm
Hi Russ - ah, now this is why I have an Internet connection; access to information and people like you.
Here's a question, re: T-33s. You'll recall that in Jan 1951 ace Don Gentile was killed in the crash of a T-33, along with his backseater, an enlisted man.
To the point of my question, I was told by a major airline maintenance type and 4th FG fan that the T-33's engine (back during that time period only?? - I forgot what he said, exactly) actually starts and runs for a short time on a different grade of fuel, but the pilot is/was required to switch to "normal" jet fuel soon afterwards to continue flight safely - otherwise a flameout may result. This same person offered this up as a possible (repeat, possible) explanation for the Gentile crash.
What do you think of this? Hogwash? Or could there be something to this 'theory'. I suppose you're the guy to ask.
Wade
PS: If this is 'hogwash', I accept responsibility for probably misunderstanding my friend's explanation.
Here's a question, re: T-33s. You'll recall that in Jan 1951 ace Don Gentile was killed in the crash of a T-33, along with his backseater, an enlisted man.
To the point of my question, I was told by a major airline maintenance type and 4th FG fan that the T-33's engine (back during that time period only?? - I forgot what he said, exactly) actually starts and runs for a short time on a different grade of fuel, but the pilot is/was required to switch to "normal" jet fuel soon afterwards to continue flight safely - otherwise a flameout may result. This same person offered this up as a possible (repeat, possible) explanation for the Gentile crash.
What do you think of this? Hogwash? Or could there be something to this 'theory'. I suppose you're the guy to ask.
Wade
PS: If this is 'hogwash', I accept responsibility for probably misunderstanding my friend's explanation.
Mon Oct 09, 2006 10:16 pm
Thanks Russ, I'll pass the info along to them....
Lynn
Lynn
Mon Oct 09, 2006 10:51 pm
Chicoartist:
Hi. Well, the engine used in 1951 was an earlier version of the J-33 engine than we had in our birds, so it may have been different, but on ours, the engine was started using a separate fuel control unit, known as the Starting Fuel Control, with the throttle in the cutoff position. After the engine lit off and progressed to a certain RPM, the throttle lever was brought "around the horn" into idle, which activated the Main Fuel Control. The Starting Fuel switch was then deactivated. There was no tankage for a different grade of fuel on our birds, and no place to mount one that I can think of. Things are packed in pretty tight. The gyro for the heading indicator system even had to be mounted in the engine bay!
I do remember reading that the early engines were very sensitive to throttle movements, and if one advanced the throttle too fast it could cause a flameout. Our aircraft had a fuel control that compensated for that. One of our ground run checks was to ram the throttle full forward as fast as you could to check this out. Always a lot of fun! One time I was doing a run in the middle of winter (which at the Griff meant 10-20 below zero!). When I did the full throttle check, the left wing suddenly dropped, almost putting the tip tank on the ground. I did a quick emergency shutdown, thinking that the turbine wheel had disintegrated and sheared off the rear fuselage or something, but it turned out that the vibration had caused the cold and brittle left main landing gear strut seals to suddenly allow the nitrogen precharge in the strut to leak out. (This is basically what happened to the Space Shuttle Challenger in 1986 when the cold seals in the solid rocket booster allowed it to leak exhaust gas.)
Hope you find this of use!
Russ
Hi. Well, the engine used in 1951 was an earlier version of the J-33 engine than we had in our birds, so it may have been different, but on ours, the engine was started using a separate fuel control unit, known as the Starting Fuel Control, with the throttle in the cutoff position. After the engine lit off and progressed to a certain RPM, the throttle lever was brought "around the horn" into idle, which activated the Main Fuel Control. The Starting Fuel switch was then deactivated. There was no tankage for a different grade of fuel on our birds, and no place to mount one that I can think of. Things are packed in pretty tight. The gyro for the heading indicator system even had to be mounted in the engine bay!
I do remember reading that the early engines were very sensitive to throttle movements, and if one advanced the throttle too fast it could cause a flameout. Our aircraft had a fuel control that compensated for that. One of our ground run checks was to ram the throttle full forward as fast as you could to check this out. Always a lot of fun! One time I was doing a run in the middle of winter (which at the Griff meant 10-20 below zero!). When I did the full throttle check, the left wing suddenly dropped, almost putting the tip tank on the ground. I did a quick emergency shutdown, thinking that the turbine wheel had disintegrated and sheared off the rear fuselage or something, but it turned out that the vibration had caused the cold and brittle left main landing gear strut seals to suddenly allow the nitrogen precharge in the strut to leak out. (This is basically what happened to the Space Shuttle Challenger in 1986 when the cold seals in the solid rocket booster allowed it to leak exhaust gas.)
Hope you find this of use!
Russ
Mon Oct 09, 2006 11:10 pm
Thanks for that, Russ. Sounds like I was basically on the right track, but that the 'switch' to the main fuel control unit on your-era jets was automatic with the throttle movement 'around the horn' after a certain RPM was achieved. You guys used the same grade fuel for starting as for normal ops, but I thought I heard that the grade was different for starting in Gentile's era (again, I might have heard wrong).
May have been that back in the day the switch between the starter and main FCU (and/or fuel grades) wasn't quite so automatic. This would mean, of course, that he was flying around for a bit on or in "starter fuel" mode.
I do remember my mech friend (lost touch since then) postulating that Gentile forgot to 'switch' and his engine flamed out - or at least that was what my friend was going to try and determine if he could find the accident report. I'm sure in this day and age it's readily available. What precipitated all this was a call to me to see if I had the serial # of Gentile's crash T-33. I do have the number (not handy), and that's when we discussed the 'possible' crash explanation.
Thanks for the "T-33 school", so far!
Wade
May have been that back in the day the switch between the starter and main FCU (and/or fuel grades) wasn't quite so automatic. This would mean, of course, that he was flying around for a bit on or in "starter fuel" mode.
I do remember my mech friend (lost touch since then) postulating that Gentile forgot to 'switch' and his engine flamed out - or at least that was what my friend was going to try and determine if he could find the accident report. I'm sure in this day and age it's readily available. What precipitated all this was a call to me to see if I had the serial # of Gentile's crash T-33. I do have the number (not handy), and that's when we discussed the 'possible' crash explanation.
Thanks for the "T-33 school", so far!
Wade
Mon Oct 09, 2006 11:13 pm
You're quite welcome!!
Russ
Russ