AN-124 - why it has to stay on the runway so long before t/o?
Fkyboyike, let's move on shall we 
I can accept what you say, it's just it's at variance with everyone else who has commented on this thread. What we need is a 124 driver, or VP8 (who I believe is very well-versed with 124/225 Ops) to settle the discussion once and for all.
Chevvron, IIRC the engine that went bang was on the port side (facing the crowdline) so wouldn't have been visible from the Tower.
Of course, that episode led to the visit of the AN-22 which pitched-up carrying the replacement donk (the following day I think). The crowds outside "The Swan" were even bigger for that one
I can accept what you say, it's just it's at variance with everyone else who has commented on this thread. What we need is a 124 driver, or VP8 (who I believe is very well-versed with 124/225 Ops) to settle the discussion once and for all.Chevvron, IIRC the engine that went bang was on the port side (facing the crowdline) so wouldn't have been visible from the Tower.
Of course, that episode led to the visit of the AN-22 which pitched-up carrying the replacement donk (the following day I think). The crowds outside "The Swan" were even bigger for that one
Last edited by Wycombe; 26th Apr 2007 at 20:46.
Yes that was my theory; the engine that went was sheilded from view and hearing in the tower.
And the AN22 when it arrived nearly didn't make it, apparently trying to land on the grass following the display line markers which, being dayglo, stood out rather well! Made the remaining spectators run for it though.
And the AN22 when it arrived nearly didn't make it, apparently trying to land on the grass following the display line markers which, being dayglo, stood out rather well! Made the remaining spectators run for it though.
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Not just the An-124
It's not just the An-124 which does this: although it has a completely different engine, I've experienced something similar when travelling as a passenger in the An-74T. Lined up on the runway threshold, it went up to what seemed like 70% of full power, and sat there for nearly three minutes, before brake release and further throttle up.
What was unusual was that in two later flights on the same aircraft that day, the delay was shorter: 2:45 on the threshold for the first flight of the day, then 2:10 for the next flight, and finally "only" 45 seconds by mid afternoon (by which time ambient temparatures were in the low 30s). Waiting for core tempatures to increase was what occurred to me as the reason.
It's an usual aircraft: high wing, with a turbofan mounted over wing.
If had been able to speak Russian, I'd probably be able to tell you more...
Shamrock
What was unusual was that in two later flights on the same aircraft that day, the delay was shorter: 2:45 on the threshold for the first flight of the day, then 2:10 for the next flight, and finally "only" 45 seconds by mid afternoon (by which time ambient temparatures were in the low 30s). Waiting for core tempatures to increase was what occurred to me as the reason.
It's an usual aircraft: high wing, with a turbofan mounted over wing.
If had been able to speak Russian, I'd probably be able to tell you more...
Shamrock
One night i was working the ramp at Sydney and noticed an AN-124 lining up on 16R, applied what seems like TO power and sat there for 15 mins, as timed by my watch. initially i thoght it was sngineers doing a high power run, but after 15 mins, with no change in power setting it began its take-off roll.
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Don't ask were I got this snipit from, and it might be total B.
During the high power on brakes phase the FE is manually adjusting the 'fuel management'
......and I do stand to be corrected
During the high power on brakes phase the FE is manually adjusting the 'fuel management'
......and I do stand to be corrected
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AN124
I was slightly involved with AN124s when in Somalia with the UN and was told by a Ukranian friend of mine that the crew calculate a power setting before take-off using normal parameters ( runway length, OAT, pressure alt. AUW etc.) then set up the engines to a calculated power setting and use the whole runway. This is to preserve the engines and avoid operating at max power.The FCUs fitted are primative by western standards hence time to achieve settings. I may be on the wrong track but it seems logical to me.
Do a Hover - it avoids G
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Some engine types have a measurable increase in thrust after the rotating components expand as they get hotter and the tip clearances (and losses) are reduced. Whether you run at high power before takeoff and wait for this improvement will clearly be affected by how much performance you desire on a particular takeoff.
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"The conspiracy theories have it that the Lotarev's on the 124 (and 225) were "heavily based" on the GE CF6, after some were acquired by the Soviets from a DC10 that was trapped on the ground in Kabul when they invaded Afghanistan!"
The Ivchenko D-18T Turbofans on the An-124 are a three shaft engine, and are more likely to resemble a RB-211 then a CF-6.
"Those with long memories will recall the early TriStars with -22B engines did the same...initially.
Rather long run-ups at partial power prior to brakes release.
Early problems (big time) with the -22B's.
I recall seeing seven of these RR engines on the ramp on engine stands at MIA in 1974.
All, and I mean all the turbine blades were...ah, gone."
The Ivchenko D-18T Turbofans on the An-124 are a three shaft engine, and are more likely to resemble a RB-211 then a CF-6.
"Those with long memories will recall the early TriStars with -22B engines did the same...initially.
Rather long run-ups at partial power prior to brakes release.
Early problems (big time) with the -22B's.
I recall seeing seven of these RR engines on the ramp on engine stands at MIA in 1974.
All, and I mean all the turbine blades were...ah, gone."
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Yeah, power assurance or slow spool to allow the turbine case to heat up, reduce wear/max thrust. Saw them do this down in Managua once. The reason others may see them turn'n burn may be light aircraft/long runway/reduced thrust t/o. Who knows? There are a ton of answers.
Their start sequence seemed like it took forever as well, they blew over a guard shack on taxi out, it was quite a show.
Their start sequence seemed like it took forever as well, they blew over a guard shack on taxi out, it was quite a show.
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My name is Ruslan but I am not An124 driver.
There was one right answer above - to reduse blade tip clearence in order to reach required power. There was a catastrophe after take off in Irkutsk wnen OAT was too low and load too high (new fighters to deliver) - clearence was big.
Why it takes so long - warm up is made two engines at a time to stay unmovable, 124 has 4.
It is one of the reasons they are forbidden to visit intensive airports.
There was one right answer above - to reduse blade tip clearence in order to reach required power. There was a catastrophe after take off in Irkutsk wnen OAT was too low and load too high (new fighters to deliver) - clearence was big.
Why it takes so long - warm up is made two engines at a time to stay unmovable, 124 has 4.
It is one of the reasons they are forbidden to visit intensive airports.
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I was at Farnborough that year too; watching the seeminlg endless run-up from the comfort of the GE Chalet, the thing I remember most as it started to move off, was the flash of flame out of the front of the nacelle just before the "Pop" reached us, follewed by a round of applause and much barely-disguised amusement from all the GE folk around me!
The consensus seemed to be that although they had made a passable job of reverse engineering the mechanicals, the FADEC was not up to the task. Apparently all attempts to purchase up to date engine managment systems from western companies, was vetoed by the US Goverment on the grounds that the technology would find its way onto the Blackjack!
The consensus seemed to be that although they had made a passable job of reverse engineering the mechanicals, the FADEC was not up to the task. Apparently all attempts to purchase up to date engine managment systems from western companies, was vetoed by the US Goverment on the grounds that the technology would find its way onto the Blackjack!
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Some years ago I followed one of these behemoths on the taxiway at CGN. We were about 200m behind all the way and just as well. As you who know Cologne airport there is a bit of an up-slope at the holding point for 24. The Antonov came to a stop, waiting for a landing aircraft then lined up. They used so much power to get moving up the slope that the RWY Marker board and the A and B marker boards got blown away to the boundary fence.
When we called the tower and told him to send the Patrol Car down to recover the debris, we were asked several times to repeat the instruction. They just couldn't understand how they would have blown away!
I wonder if they sent them the bill for the new lights and boards?
When we called the tower and told him to send the Patrol Car down to recover the debris, we were asked several times to repeat the instruction. They just couldn't understand how they would have blown away!
I wonder if they sent them the bill for the new lights and boards?
