777 down.
- Thread starter empip
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I can assure you Noseall that the pilots certainly DO touch the controls and the engines are at full wet thrust ... It's not just the catapault that gets them airborne.
I have read about this in a few places and it is not accurate...
They do a normal powered approach (much flatter than normal, higher angle of attack and higher power settings) with the engines running dry (no reheat) at around 60% with the major difference being that there is no flare before impact they simply fly down the glideslope until the carrier gets in the way and they hit it.
Now the bit you've probably picked up on is that, just prior to touchdown, the pilot will select full dry throttle and the engines will start to spool up ... He returns the throttle to idle once he feels the pull of the arrester wires which, in reality, is split seconds. If he forgets to close the throttles the arrestor wire is fully capable of stopping the aircraft with the engines at max. This is an extremely odd thing for a pilot to do and takes some discipline as it is the opposite of what you'd normally do.
The reason for this is that gas turbines are (relatively) slow to spool up from idle but fast enough from 70% to be capable of reaching full thrust (including reheat) on a carrier for an aborted landing.
During the landing phase airspeed is controlled by angle of attack whilst rate of descent is controlled by engine power and you would not get a fighter anywhere near the carrier with the engines running at 100%
You go from around 150 mph to a dead stop in just over over a second ... It's an awesome feeling which I have been lucky enough to experience and I had bruises across my shoulders from the harness after the first landing
This video shows it all pretty well and you can hear the engines spool up at touchdown ... I'd say the pilot was a little twitchy as he kept the power on longer than I'd expect
http://www.metacafe.com/watch/303345/carrier_landing_home_video/
MW
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all the footage of fighter pilots taking off aboard ship show them clearly and deliberately taking their hands off the controls at the point of take off.
in fact they have to show the deck controller their hands to be allowed to take off, and this is visible through the cockpit glass. they should NOT be on the controls.
this is so that the computer has control at the point or take off.
the pilot has control AFTER this point.
in fact they have to show the deck controller their hands to be allowed to take off, and this is visible through the cockpit glass. they should NOT be on the controls.
this is so that the computer has control at the point or take off.
the pilot has control AFTER this point.
Are you confusing wheel speed with forward speed or air speed of the aircraft? If the aircraft were travelling forward relative to a fixed point at a speed of 100mph and the conveyor was travelling backwards at the same speed, then yes the wheel speed would be 200mph. However the OP states that the conveyor will match the wheel speed of the aircraft, not the speed of the aircraft itself.
Well we are already have to ignore the practicalities of the conveyor, but how fast the wheels would need to be turning to absorb enough energy to match the finite engine thrust, I don't know. It would have to be be extremely fast, but not necessarily infinite.
This is a classic example of people misinterpreting what they are seeing ...
This is the signal to the shooter that they are ready to roll and was brought in following a number of incidents in the early days where jets were launched before the pilot was ready. The instinctive reaction is to pull back on the stick which can result in the catapault disengaging ... And the jet going over the side.
Yes, but for the reason I have described above, not because the computer is taking control of the aircraft.
Absolutely 100% not
Name me one aircraft in production today where the on-board flight management system is capable of taking off the aircraft and (if you manage to pick the odd few) take a guess at whether it is certified for use by the CAA and FAA and, therefore, estimate how frequently it is used.
95% of aircraft currently carrier based have no such capability so I'm not sure where you dreamed this one up from.
The take off phase is the most dangerous aspect of flight and one where pilots are always in control and always at the highest level of concentration in preparation for the unexpected.
The pilot is in control ALL the time they are simply trained to resist the temptation to pull back on the stick until they reach the departure threshold ... Not because of computer controls or any such wizardry ... Simply so that they don't disengage the catapault
On all my flights I can assure you that both the pilot in command had one hand on the stick and the other on the throttle during every take off as is the case on every take off on every flight everywhere ... It is standard flight practice and for good reason.
MW
Says who?
Marginally but it is by no means directly proportional as it is a factor of resistance to inertial movement (environment) and resistance of components (bearings etc) ... We can assume the former is static and that the dynamic component (the additional speed of the conveyor) is only dependant upon the latter which is negligable.
I was going to draw and post a diagram to show how the inertial forces generated by the engine thrust are not relative to the ground but Softus has explained this better than I could have.
In this scenario there is no way that the rolling resistance on the wheel bearings could ever amount to the order of thrust produced by the aircraft's engine(s) ... Trents produce up to 74,000lbs
There is a very real likelyhood that the bearings would seize, the heat packs would catch fire and the whole thing would crash and burn but that isn't the crux of the OP's question.
Practically or theoretically Blondini the aircraft's airborne.
MW
Doesn't most of the rolling resistance come from the tyres? I agree that it is a small amount relative to the available engine thrust, but if you double a small amount and keep doubling it, you very quickly arrive at a large amount. The conyeyor in the OP has no limit other than it can match the wheel speed. It can double it's speed as many times as you like.
Give it up Blondini as you're talking boll***s
Let's not get the thread locked. Please.
No. I can scarcely believe that you don't understand this.
The wheel speed is directly proportional to the aircraft speed. If the aircraft doubles its speed, then the wheels double in speed.
No - it's possible only in your imagination, which is not the same as being theoretically possible. However, a theory can be proven by showing the working, so if you have such a theory then please show the working.
I know that you don't know - this is why you've arrived at the wrong answer.
No it wouldn't - it would have to be twice as fast as normal. Whatever speed the plane is moving, if the conveyor matches either plane or wheel speed, then the wheels will be rotating twice as fast as they would if there were no conveyor there.
Work is pressing. I'll have a think about this and come back later.
Chocks away
Chocks away
Nobody mentioned chocks ... Now if we are using chocks that's a different story
Rather than have a rather abstract think, which generally doesn't result in anything useful in your case, why don't you read back through the thread and try to take in what people have already posted ... The time you will save will preserve a few brain cells which would otherwise have perished.
You do appear to need them
MW
Rather than have a rather abstract think, which generally doesn't result in anything useful in your case, why don't you read back through the thread and try to take in what people have already posted ... The time you will save will preserve a few brain cells which would otherwise have perished.
You do appear to need them
MW
http://www.metacafe.com/watch/74382/f_a_18_crash/
crash bang wollop!
crash bang wollop!
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