A/c train From United Kingdom, joined Jun 2001, 501 posts, RR: 4 Reply 3, posted (12 years 9 months 2 days 15 hours ago) and read 1422 times:
On the A300 600R there is a PTU on the blue system driven by the green system which is used in event of a left engine failure or on the ground and there is also one on the yellow system , the pump output on the PTU is about 90 1/min at standard system pressure 3000 psi .
Oldman From United States of America, joined Sep 2006, 0 posts, RR: 0 Reply 4, posted (12 years 9 months 2 days 15 hours ago) and read 1419 times:
Airtrain, JG answered that post above yours. 3000 PSI. Period! He did not want to know any more detail. I'll bet if everyone would look before they leap and just reply to specifics this forum would download much faster.
HeavyJet From , joined Dec 1969, posts, RR: Reply 5, posted (12 years 9 months 2 days 14 hours ago) and read 1422 times:
I agree that some people seem to try and impress everyone with their system knowledge by adding superfluous information which exceeds the original poster's question. However, I can just about guarantee the next question from someone would be, "what's a PTU?".
Couple of things...
First, since just about EVERY subject has been discussed to death on these forums. I think it would greatly cut down on the number of post if folks would simply do a "search" before asking a question.
What's a 16-20 yr old doing with a Airbus FCOM and why would you want to spent your free time reading one? Doesn't anyone get out and play sports anymore?!?
FDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 36 Reply 6, posted (12 years 9 months 2 days 12 hours ago) and read 1413 times:
Something odd yet consistant I've noticed with the G/B & G/Y A300-600 PTU's (HeavyJet, perhaps you can check this on your aircraft).
When I run for example the green/blue PTU, the green system is 3000 psi but the blue is 3100 psi. This is odd in the fact that the green system is driving the blue sys. Conventional wisdom being that the system being driven wouldn't produce more pressure than the system driving it.
Oldman From United States of America, joined Sep 2006, 0 posts, RR: 0 Reply 7, posted (12 years 9 months 2 days 12 hours ago) and read 1410 times:
HeavyJet, I agree with you 100% At the start of the forum it says for advanced professional and knowledgeable amateurs. We both remember when this stuff was relevant. All the numbers and pressure settings etc. Then that took a back seat, and oral questions would be, "What is the oil over heat limit? Ans. in the red. And now not even that, just click a page and the system displays right there. Who cares unless your going to build one!
By the way, you must have a day off? Thought you guys slept all day? Regards, Oldman
Sabenapilot From Belgium, joined Feb 2000, 2712 posts, RR: 48 Reply 12, posted (12 years 9 months 2 days 1 hour ago) and read 1383 times:
I don't know if you know this, but in general the hydraulic pressure on all planes is around 3000 psi!
This has everything to do with the fact that this provides you with a good/fast operating system shaped into acceptable dimentions and with a fairly low weight.
Lower pressure would reduce the weight of the system due to the fact that is has to be less strong, but it would also reduce the efficiency and increase the response time.
Higher pressure would reduce the response time and increase the efficiency, but it would also force us to make the system much havier in order to resist the higher pressure forces.
VC-10 From United Kingdom, joined Oct 1999, 3691 posts, RR: 35 Reply 14, posted (12 years 9 months 2 days ago) and read 1382 times:
Airbus PTU's are gutless compared to DC10 reversable motor pumps. I recall in my A310 days trying to function chk the Wing Tip Brakes. With the flaps & slats operating on the elect pumps & PTU there was not enough press left to actuate thw WTB's. On the DC10 you could operate all the high hydraulic flow rate flight controls at the same time and not loose more than about 750 psi.
Regarding training I remember when I took my RR Spey type licence the CAA surveyor gave me a sectioned picture of the Combined Acceleration & Speed Control Unit (FCU) and I had to explain how it worked. These days if you ask an instructor how something works you are told "just fine"
Oldman From United States of America, joined Sep 2006, 0 posts, RR: 0 Reply 16, posted (12 years 9 months 1 day 18 hours ago) and read 1364 times:
Off we go again? Please read the original question, then the first reply by someone named JG. Then please read the reply by HeavyJet. A simple answer was all the orig. post asked. Let us all not try to re invent the wheel. Cheers
A/c train From United Kingdom, joined Jun 2001, 501 posts, RR: 4 Reply 19, posted (12 years 9 months 1 day 14 hours ago) and read 1353 times:
Hey lets not make this into a winging forum us amateurs are on the site to learn from the people who have been there and done it, but I do agree the awnsers should be brief and just to the point and I dont have an A300 FCOM and I certainly have limited system knowledge I have just learnt it.
Avt007 From Canada, joined Jul 2000, 2132 posts, RR: 5 Reply 22, posted (12 years 9 months 1 day 7 hours ago) and read 1343 times:
Oldman,heavyjet; If everyone restricted themselves to doing searches, or one-answer posts, this forum would shrivel up and die. As it is , you can check it once or twice a week, and little has been posted. If someone asks a question previously covered, you aren't obligated to answer! If folks want to put in their two cents worth, more power to them! What else is this site here for?