May 18, 2011, 09:44:00 GMT
permalink Post: 6457895
.... brakes set to park and all wheels chocked
4 years ago Spanner Turner came to my rescue on ground runs with -
Quote below is from the Maintenance Manual. (a 747 manual, but you get the picture).
C. Prepare for Engine Operation.
(1) Check that airplane is parked in clean area with wheels on areas
that are free of oil, grease, or other slippery substances.
(2) Make sure the wheel chocks are installed at the main landing gear
wheels and ground locks are installed.
(a) Do these steps if you will operate the engines for a high power
engine run.
1) Make sure that the forward wheel chock is six to twelve
inches in front of the tires.
NOTE: This will cause the thrust of the engine to be held
by the frictional force between the airplane tires and the
ground, and not the wheel chock. The wheel
chocks do not have the same frictional force as the
tires. If the tires touch the wheel chock, some of
the frictional force between the tires and the
ground is lost, and the airplane can skid. The
wheel chocks are only used to prevent the airplane
from rolling if the airplane brakes were
accidentally released before or after the engine run.
Subjects
Boeing 747
Braking
Landing Gear
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February 21, 2012, 15:23:00 GMT
permalink Post: 7040634
Someone I know said he flew Miami to Washington and then on to London on Concorde. He said the turn around time at Washington was only 30 mins. The leg from Miami to Washington was partially supersonic. This seems to be hard to believe, as I know it takes the best part of an hour to refuel a 747. Surely topping off the tanks on Concorde would take more than 30 mins????
Subjects
Boeing 747
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April 26, 2012, 20:22:00 GMT
permalink Post: 7157964
Many thanks for this thread. Thank heavens Concorde didn't have an APU otherwise I wouldnt have had the pleasure of reading it.
I was at school in Basingstoke when Concorde first attended the Farnborough air show. Maths lessons were constantly interrupted by the third floor windows filling up with a very noisy aeroplane flying over at high alpha and wheels down. After the third circuit, the teacher (an Australian,) shouted at us that we'd seen your BXXXdy aeroplane now get back to work. Phillistine!
I never saw one flying without looking up in reverent awe and I cannot recall a time when anybody else wasn't doing so.
Came the day that I woke up to hear the sad news on the morning radio of the retirement. I emailed my comment and it was read out on the Today programme. Looking on the 'net at work at the other comments there was a small window telling me that BA were offering celebration flights. 1,000 tickets at \xa32,000 a go.
I'd just bought a house and my meagre savings were needed for a bathroom, hot water and some further essentials. I held out until tea break and dialled There were three tickets left. Make that two, please. I booked the first flight I could get in case something went wrong and the project was canned early.
Paying was another matter. All my money was in France and the BA desk at Southampton wouldn't take my cheque so I transferred money to my British account and tried it again. "There must be some mistake" said the nice lady at the desk. "This booking ref is coming up very expensive. I'm going to see if I can get it cheaper."
"Please don't." I replied.
"But you don't understand, This flight is VERY expensive. "I know." The people behind me were becoming disgruntled.
"I just don't get it. What class are you travelling?"
"Concorde."
The people behind me suddenly backed off.
I had a good trip out, my first trip on a 747. Ask for a Whiskey and get a nice little bottle of Johnny Walker.
I had a better trip back. Ask for a Whiskey and get enough eighteen year old Glenfiddich to drown a small child.
The experience changed my life. The only thrill that could get anywhere near it would be to pilot an aircraft myself. I now have about eight hours solo. It doesn't compare. Being SLF on Alpha Golf was the thrill of a lifetime and I have never regretted a penny of it.
To those contributors who worked on the programme in any capacity, Thank you for the enormous priviledge of being able to experience such a fine and beautiful thing.
Having rambled on for far too long already, I'll just recall a line from Radio 4's Week Ending: "Following a question in the House, the minister admitted that Concorde made more noise than the Bay City Rollers but pointed out that it was of far better quality."
I was at school in Basingstoke when Concorde first attended the Farnborough air show. Maths lessons were constantly interrupted by the third floor windows filling up with a very noisy aeroplane flying over at high alpha and wheels down. After the third circuit, the teacher (an Australian,) shouted at us that we'd seen your BXXXdy aeroplane now get back to work. Phillistine!
I never saw one flying without looking up in reverent awe and I cannot recall a time when anybody else wasn't doing so.
Came the day that I woke up to hear the sad news on the morning radio of the retirement. I emailed my comment and it was read out on the Today programme. Looking on the 'net at work at the other comments there was a small window telling me that BA were offering celebration flights. 1,000 tickets at \xa32,000 a go.
I'd just bought a house and my meagre savings were needed for a bathroom, hot water and some further essentials. I held out until tea break and dialled There were three tickets left. Make that two, please. I booked the first flight I could get in case something went wrong and the project was canned early.
Paying was another matter. All my money was in France and the BA desk at Southampton wouldn't take my cheque so I transferred money to my British account and tried it again. "There must be some mistake" said the nice lady at the desk. "This booking ref is coming up very expensive. I'm going to see if I can get it cheaper."
"Please don't." I replied.
"But you don't understand, This flight is VERY expensive. "I know." The people behind me were becoming disgruntled.
"I just don't get it. What class are you travelling?"
"Concorde."
The people behind me suddenly backed off.
I had a good trip out, my first trip on a 747. Ask for a Whiskey and get a nice little bottle of Johnny Walker.
I had a better trip back. Ask for a Whiskey and get enough eighteen year old Glenfiddich to drown a small child.
The experience changed my life. The only thrill that could get anywhere near it would be to pilot an aircraft myself. I now have about eight hours solo. It doesn't compare. Being SLF on Alpha Golf was the thrill of a lifetime and I have never regretted a penny of it.
To those contributors who worked on the programme in any capacity, Thank you for the enormous priviledge of being able to experience such a fine and beautiful thing.
Having rambled on for far too long already, I'll just recall a line from Radio 4's Week Ending: "Following a question in the House, the minister admitted that Concorde made more noise than the Bay City Rollers but pointed out that it was of far better quality."
Last edited by m.Berger; 26th April 2012 at 20:25 . Reason: Spelling
Subjects
APU (Auxiliary Power Unit)
Boeing 747
British Airways
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April 28, 2012, 21:29:00 GMT
permalink Post: 7161124
For some reason I seem to remember a picture of a Concorde Cockpit with four INS sets side by side, was this ever the case or just my imagination ?
Also, were the INS installed specially developed for Concorde or were they the same as fitted in the B747 for example.
Finally was GPS updating to the INS position ever developed and installed ?
Also, were the INS installed specially developed for Concorde or were they the same as fitted in the B747 for example.
Finally was GPS updating to the INS position ever developed and installed ?
Subjects
Boeing 747
INS (Inertial Navigation System)
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April 29, 2012, 19:13:00 GMT
permalink Post: 7162482
For some reason I seem to remember a picture of a Concorde Cockpit with four INS sets side by side, was this ever the case or just my imagination ?
Also, were the INS installed specially developed for Concorde or were they the same as fitted in the B747 for example.
Finally was GPS updating to the INS position ever developed and installed ?
Very relevant for the current time: it was a similar INS system that was hashed into the Vulcan to allow it to find the falklands for the blackbuck raids.
Subjects
Boeing 747
Captains
G-AXDN
G-BBDG
INS (Inertial Navigation System)
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July 16, 2012, 08:08:00 GMT
permalink Post: 7297980
the best thread ever on the net and so polite.
all those technicals and in deep infos.
i never flown myself the Concorde but my dad made one CDG DKR RIO and one CDG JFK and as others mention he was smiling back from those flights even the flights were for work.
i had the chance to see the Concorde at night in the AF maintenance at CDG it was called Airbus-Concorde division and despite i was more on the other side : the 747 division i loved to stay around and just watching that wonderful Bird waiting to fly the next morning.
alas when moving to Canada we lost all the pictures and souvenirs of those days but they re back with you.
thank you Lady and Gentlemen.
and Bravo, merci.
all those technicals and in deep infos.
i never flown myself the Concorde but my dad made one CDG DKR RIO and one CDG JFK and as others mention he was smiling back from those flights even the flights were for work.
i had the chance to see the Concorde at night in the AF maintenance at CDG it was called Airbus-Concorde division and despite i was more on the other side : the 747 division i loved to stay around and just watching that wonderful Bird waiting to fly the next morning.
alas when moving to Canada we lost all the pictures and souvenirs of those days but they re back with you.
thank you Lady and Gentlemen.
and Bravo, merci.
Last edited by phil@LFPG; 16th July 2012 at 08:09 .
Subjects
Air France
Boeing 747
CDG
JFK
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October 18, 2013, 22:40:00 GMT
permalink Post: 8106344
BA was able to make money on Concorde as in positive cash flow. But they were basically given the airplanes. The commercial failure aspect comes from the simple fact that no one wanted them to build any more (what I've heard is that at least one production Concorde was built but never put into service - basically becoming a donor for spares - not sure if that's true).
I also suspect it was too much of a point design - it didn't have the range to be useful in the Pacific.
CONCORDE SST : CONCORDE B
If BA (and Air France) honestly thought Concorde was a profit center (rather than brand prestige), they would have wanted more
.
.
The same thing would have applied to the Boeing SST if it hadn't been cancelled (I knew a guy that worked on the Boeing SST inlet control system - talk about complex
). Cancelling the SST is probably the best thing that ever happened to Boeing - it likely would have bankrupted the company.
). Cancelling the SST is probably the best thing that ever happened to Boeing - it likely would have bankrupted the company.
Last edited by DozyWannabe; 18th October 2013 at 23:02 .
Subjects
Boeing
Boeing 747
Boeing SST
British Airways
Brooklands
G-BBDG
Intakes
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October 19, 2013, 01:14:00 GMT
permalink Post: 8106489
The Concorde and Boeing SST business cases were built on a couple flawed assumptions.
First, jet fuel would remain dirt cheap and the higher fuel burn of supersonic travel not contribute significantly to cost of operation - which was blown out of the water by the first Arab oil embargo.
Second, that the majority of demand for air travel would remain for the 'premium' product - basically that the majority of people would happily pay a premium to get there faster. This assumption applied to most people who flew on jets in the 1960's - either business travelers or well to do people that weren't that worried about what it cost.
Reality was it went the opposite direction - a shift that started with the 747 and other widebodies. The economies of the wide body aircraft lowered the cost of air travel to the 'everybody' level. Suddenly there was a whole new class of air traveler - people for whom an extra $100 airfare meant they just wouldn't go, never mind that they'd get there in half the time. In short, they didn't foresee air travel becoming just another commodity - the low cost trend that continues today.
The reality was, both the Concorde and the SST needed to sell hundreds of copies to even begin to justify the development costs. The evolution of air travel into a low cost commodity, combined with the rising costs of jet fuel, insured that would never happen.
First, jet fuel would remain dirt cheap and the higher fuel burn of supersonic travel not contribute significantly to cost of operation - which was blown out of the water by the first Arab oil embargo.
Second, that the majority of demand for air travel would remain for the 'premium' product - basically that the majority of people would happily pay a premium to get there faster. This assumption applied to most people who flew on jets in the 1960's - either business travelers or well to do people that weren't that worried about what it cost.
Reality was it went the opposite direction - a shift that started with the 747 and other widebodies. The economies of the wide body aircraft lowered the cost of air travel to the 'everybody' level. Suddenly there was a whole new class of air traveler - people for whom an extra $100 airfare meant they just wouldn't go, never mind that they'd get there in half the time. In short, they didn't foresee air travel becoming just another commodity - the low cost trend that continues today.
The reality was, both the Concorde and the SST needed to sell hundreds of copies to even begin to justify the development costs. The evolution of air travel into a low cost commodity, combined with the rising costs of jet fuel, insured that would never happen.
Last edited by tdracer; 19th October 2013 at 01:18 . Reason: edited to fix typos
Subjects
Boeing
Boeing 747
Boeing SST
Fuel Burn
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October 19, 2013, 01:56:00 GMT
permalink Post: 8106519
The Concorde and Boeing SST business cases were built on a couple flawed assumptions.
First, jet fuel would remain dirt cheap and the higher fuel burn of supersonic travel not contribute significantly to cost of operation - which was blown out of the water by the first Arab oil embargo.
First, jet fuel would remain dirt cheap and the higher fuel burn of supersonic travel not contribute significantly to cost of operation - which was blown out of the water by the first Arab oil embargo.
Second, that the majority of demand for air travel would remain for the 'premium' product - basically that the majority of people would happily pay a premium to get there faster. This assumption applied to most people who flew on jets in the 1960's - either business travelers or well to do people that weren't that worried about what it cost.
Reality was it went the opposite direction - a shift that started with the 747 and other widebodies. The economies of the wide body aircraft lowered the cost of air travel to the 'everybody' level. Suddenly there was a whole new class of air traveler - people for whom an extra $100 airfare meant they just wouldn't go, never mind that they'd get there in half the time. In short, they didn't foresee air travel becoming just another commodity - the low cost trend that continues today.
The reality was, both the Concorde and the SST needed to sell hundreds of copies to even begin to justify the development costs. The evolution of air travel into a low cost commodity, combined with the rising costs of jet fuel, insured that would never happen.
Subjects
Afterburner/Re-heat
Airbus
Boeing
Boeing 747
Boeing SST
Fuel Burn
Sidestick
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July 23, 2014, 23:41:00 GMT
permalink Post: 8577184
It's a fascinating posit, and one for aviation nerds to discuss at length down the pub - I'll give it that!
The general trend follows, but he doesn't spend much time on external factors (such as the 747's degree of success being aided significantly by the tribulations of Lockheed's L1011 development and MD's reaction to the DC-10's flaws).
It's interesting that the article writer seized on the paragraph about Concorde to frame his article though - it's almost a footnote in the original journal piece!
The general trend follows, but he doesn't spend much time on external factors (such as the 747's degree of success being aided significantly by the tribulations of Lockheed's L1011 development and MD's reaction to the DC-10's flaws).
It's interesting that the article writer seized on the paragraph about Concorde to frame his article though - it's almost a footnote in the original journal piece!
Subjects
Boeing 747
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July 28, 2014, 11:33:00 GMT
permalink Post: 8583277
Evolution: Survival of the fittest.
An often misunderstood expression.
Fittest does not mean the most athletic or physically strong, it means fit for it's environment.
When the environment changes the animal/plant/aircraft needs to evolve to best fit that changing environment.
Living organisms take many generations to change due to the randomness of genetic mutation. Aircraft design, in comparison, changes relatively quickly as new technology and ideas develop.
The environment changed in the seventies, fuel prices exploded. The 747, and continued lines of fuel efficient wide bodies thrived, Concorde only continued due to political will. If the price of fuel was still $20/barrel Concorde (and probably a couple of successors) would be going strong as it would still "fit" the political and economic environment. (The greens may have put a bit of pressure on though
)
Simples eh?
An often misunderstood expression.
Fittest does not mean the most athletic or physically strong, it means fit for it's environment.
When the environment changes the animal/plant/aircraft needs to evolve to best fit that changing environment.
Living organisms take many generations to change due to the randomness of genetic mutation. Aircraft design, in comparison, changes relatively quickly as new technology and ideas develop.
The environment changed in the seventies, fuel prices exploded. The 747, and continued lines of fuel efficient wide bodies thrived, Concorde only continued due to political will. If the price of fuel was still $20/barrel Concorde (and probably a couple of successors) would be going strong as it would still "fit" the political and economic environment. (The greens may have put a bit of pressure on though
)
Simples eh?
Subjects
Boeing 747
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April 08, 2015, 20:40:00 GMT
permalink Post: 8937224
Ruddman -
No autobrakes.
(And - with my pedant's hat on - no 'manual' brakes either. Pedal brakes, yes. I know that the 'manual brakes' has become an accepted term, but the nonsense of it just bugs me….)
Stopping distances were good; from a higher Vapp we stopped rather shorter than a 'classic' 747. Filton was tightish, Bournemouth was worse….
First gen carbon brakes did not like being 'feathered' so we used them pretty firmly on every landing. At Filton, Bournemouth, E Midlands etc. you'd put the pedals to the floor after nose wheel touchdown. Allegedly no more wear doing this than feathering them along a long runway.
Reverse was pretty effective - more so than a modern bypass engine. We idled the outboards at 100kts and the inboards at 75kts so they weren't in play for the whole landing (reverse is most effective at higher speeds anyway).
It was a good 'stopper'. Thankfully.
No autobrakes.
(And - with my pedant's hat on - no 'manual' brakes either. Pedal brakes, yes. I know that the 'manual brakes' has become an accepted term, but the nonsense of it just bugs me….)
Stopping distances were good; from a higher Vapp we stopped rather shorter than a 'classic' 747. Filton was tightish, Bournemouth was worse….
First gen carbon brakes did not like being 'feathered' so we used them pretty firmly on every landing. At Filton, Bournemouth, E Midlands etc. you'd put the pedals to the floor after nose wheel touchdown. Allegedly no more wear doing this than feathering them along a long runway.
Reverse was pretty effective - more so than a modern bypass engine. We idled the outboards at 100kts and the inboards at 75kts so they weren't in play for the whole landing (reverse is most effective at higher speeds anyway).
It was a good 'stopper'. Thankfully.
Subjects
Boeing 747
Braking
Filton
Landing Gear
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January 07, 2016, 19:15:00 GMT
permalink Post: 9231663
How exactly would you get the INS into memory mode so you could input the two digit code to activate the route section.
Subjects
Boeing 747
INS (Inertial Navigation System)
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February 02, 2016, 12:02:00 GMT
permalink Post: 9256478
A very belated reply.
I'm not really sure why I stopped coming here, it is one of, if not
the
most interesting thread on any of the forums I visit - by miles. However, I got back into it a few days ago and realised I was over a hundred
pages
behind. I have been slowly catching up, but I'm still nearly fifty pages behind.
My first question is; what has become of the Brabazon Hangar/ BAe Filton/ G-BOAF situation? Wikipedia just say its all been sold - the airfield at least - but not what the dispositions of all those valuable items, particularly Alpha Foxtrot.
Second, just to show I really am reading myself back up to date, I noticed something ChristaanJ said that has some resonance with me.
Wow! Yes I have CJ! I only know one other person who has - fascinating book and I know exactly what you mean. Thee are several other books in the same vein;
21st Century Jet
- about the conception and birth of the Boeing 777 and
Wide Body
, the equally fascinating story of the beloved and iconic Boeing 747.
You probably don't remember, but I used to be a "scanner engineer" - I finally retired in July last year - but I was involved in the very early days of what are now common place diagnostic machines. At some point in the early nineties, I realised two things. I could write a bit - not incomprehensibly at any rate - and all the people who made the early scanners, did the development work and worked on them in the field before me, were either retired or passed away. I asked the management at the time if I could have a bit of time, perhaps a half day every week, to do the research and do a 'Tracy Kidder' for the EMIScanner. No answer came the stern reply and it never got done. Now I don't think it can be, so it never will.
I would love to write 'The Soul of a New Machine' for Concorde, but A) I'm probably too old now and B) I was never part of it, so I probably can't put the passion in to it, certainly not the knowledge, that she deserves.
If anyone on here who was part of it who wants to put pen to paper (Oh come on! Who doesn't use a Word Processor - which dates me on its own!) but it doesn't seem to come out right, perhaps we ought to meet?
Few of my close friends are engineers or scientists and although they all agree that Concorde was (and is) a lovely looking thing, they simply don't understand why it is that engineers get passionate and dewy eyed about her. They cannot comprehend the difficulties of flying at Mach 1+, let alone Mach 2 for three hours in a pretty frock and thus, the ability to do so just seems 'normal'. The book is there to write; the book of the people, by the people, for the people.
My first question is; what has become of the Brabazon Hangar/ BAe Filton/ G-BOAF situation? Wikipedia just say its all been sold - the airfield at least - but not what the dispositions of all those valuable items, particularly Alpha Foxtrot.
Second, just to show I really am reading myself back up to date, I noticed something ChristaanJ said that has some resonance with me.
Quote:
Has anybody here read "The Soul of a New Machine", by Tracy Kidder?
It's a pity no book quite like that has ever been written about Concorde... and I can't imagine it could be written today. Too many of the 'actors' have retired, or are not there anymore....
Maybe somebody ambitious could use this thread as a base, and do some interviews, and write "Concorde, From Then to Now" ?
Has anybody here read "The Soul of a New Machine", by Tracy Kidder?
It's a pity no book quite like that has ever been written about Concorde... and I can't imagine it could be written today. Too many of the 'actors' have retired, or are not there anymore....
Maybe somebody ambitious could use this thread as a base, and do some interviews, and write "Concorde, From Then to Now" ?
You probably don't remember, but I used to be a "scanner engineer" - I finally retired in July last year - but I was involved in the very early days of what are now common place diagnostic machines. At some point in the early nineties, I realised two things. I could write a bit - not incomprehensibly at any rate - and all the people who made the early scanners, did the development work and worked on them in the field before me, were either retired or passed away. I asked the management at the time if I could have a bit of time, perhaps a half day every week, to do the research and do a 'Tracy Kidder' for the EMIScanner. No answer came the stern reply and it never got done. Now I don't think it can be, so it never will.
I would love to write 'The Soul of a New Machine' for Concorde, but A) I'm probably too old now and B) I was never part of it, so I probably can't put the passion in to it, certainly not the knowledge, that she deserves.
If anyone on here who was part of it who wants to put pen to paper (Oh come on! Who doesn't use a Word Processor - which dates me on its own!) but it doesn't seem to come out right, perhaps we ought to meet?
Few of my close friends are engineers or scientists and although they all agree that Concorde was (and is) a lovely looking thing, they simply don't understand why it is that engineers get passionate and dewy eyed about her. They cannot comprehend the difficulties of flying at Mach 1+, let alone Mach 2 for three hours in a pretty frock and thus, the ability to do so just seems 'normal'. The book is there to write; the book of the people, by the people, for the people.
Subjects
Boeing
Boeing 747
Filton
G-BOAF
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October 12, 2019, 23:49:00 GMT
permalink Post: 10593003
Pattern, I didn't bother to address the viability question, but unless there is a massive technological breakthrough we're not going to see another commercial SST. The costs and fuel burn of an SST compared to a conventional subsonic airliner make the potential number of paying passengers too small for it to be economically viable. There simply are not that many people who are willing
and
able to pay a massive price premium to save a couple hours of flight time. No matter how efficient the engines and the airframe, fuel burn is always going to be much higher going supersonic (as one of my college professors put it, 'it takes a lot of energy to break windows ten miles below'), and the stresses of supersonic flight mean high maintenance costs.
The one possibility for a future supersonic passenger aircraft is for a (relatively) small biz jet. Something targeted for the super rich who are willing and able to pay a huge premium to save a few hours (I'm talking about the sort of people who have a 747 as their private jet). The business case would have to assume a small production run (less than 100 aircraft) meaning the massive nonrecurring development and certification costs would need to be spread over a correspondingly small number of sales. On the plus side, the biz jet regulations are somewhat more forgiving than those for large commercial aircraft (i.e. Part 25).
The one possibility for a future supersonic passenger aircraft is for a (relatively) small biz jet. Something targeted for the super rich who are willing and able to pay a huge premium to save a few hours (I'm talking about the sort of people who have a 747 as their private jet). The business case would have to assume a small production run (less than 100 aircraft) meaning the massive nonrecurring development and certification costs would need to be spread over a correspondingly small number of sales. On the plus side, the biz jet regulations are somewhat more forgiving than those for large commercial aircraft (i.e. Part 25).
Subjects
Boeing 747
Fuel Burn
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June 25, 2022, 00:14:00 GMT
permalink Post: 11251293
Point taken GF, but it was discovered during development flying that that the Olympus 593 could be relit, given sufficient IAS, at almost any altitude within the normal flight envelope. The variable inlet would even be automatically scheduled, as a funcion of N1, in order to improve relight performance at lower Mach numbers. I certainly agree that you would decelerate and lose altitude fairly quickly under these conditions, however a multiple flame out was never experienced during the entire 34 years of Concorde flight testing and airline operation. There was, as a matter of interest an un-commanded deployment of a Concorde RAT AT MACH 2!! (The first indications of the event were when the cabin crew complained about 'a loud propeller sound under the rear cabin floor'. A quick scan of the F/E's panel revealed the truth of the matter). The aircraft landed at JFK without incident, and the RAT itself, apart from a very small leak on one of the hydraulic pumps, was more or less un-phased by the event. Although it sounds horrific, a prop rotating in a Mach 2 airstream, the IAS it 'felt' would be no more than 530 KTS at any time. The RAT was of course replaced before the aircraft flew back to LHR.
Not quite sure about your reference to the RAT on an F16 being Hydrazine powered; a Ram Air Turbine is just that, using the freely rotatting propellor to power hydraulics, electrics or both. Or do you mean the the F16 has an emergency power unit? Either way, it's fascinating stuff.
Yes, I do remember that the Germans used Hydrazine as a fuel during WW2: The father of one of our Concorde pilots was on an air raid to destroy one o the production plants there, this aviation business is such a small world.
Not quite sure about your reference to the RAT on an F16 being Hydrazine powered; a Ram Air Turbine is just that, using the freely rotatting propellor to power hydraulics, electrics or both. Or do you mean the the F16 has an emergency power unit? Either way, it's fascinating stuff.
Yes, I do remember that the Germans used Hydrazine as a fuel during WW2: The father of one of our Concorde pilots was on an air raid to destroy one o the production plants there, this aviation business is such a small world.
What I found interesting is that the AC generators would remain on-line at all; they drop instantaneously at subsonic speeds and the associated N2 rpm. I believe the hydraulics on the 747 will power flight controls down to a pretty low IAS.
Four engine flameout is a very unlikely event, unless one runs into a volcanic cloud.
Subjects
Boeing 747
Cabin Crew
Flameout
Flight Envelope
Hydraulic
Hydrazine
IAS (Indicated Air Speed)
Intakes
JFK
LHR
N1 (revolutions)
Olympus 593
RAT (Ram Air Turbine)
Relight
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November 11, 2023, 05:56:00 GMT
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My question is why couldn't they maintain altitude
For the weight they were at the zero rate of climb speeds were,
Gear Retracted - 0ne engine out 193kt - Two engines out 262kt
Gear Extended (the condition they were in) - One engine out 205kt - Two engines out >300kt
They had two engines effectively out.
Subjects
Air France 4590
Boeing 747
V2
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