www.expressandstar.com/news/crime/2012/08/15/jail-term-looms-for-raids-getaway-driver/
Jail for car thief who outran a police helicopter capable of 180mph
Last edited by: VxFan on Thu 16 Aug 12 at 01:37
|
What a load of hogwash.
On what motorway could you do a constant 180mph?
At that speed, how long before you'd run out of fuel?
Helicopters can fly straight, whilst m/ways bend more than you'd imagine.
Would a helicopter in one force, not alert one in the next?
|
|
Ah but it had flames coming out of the back.
|
>> What a load of hogwash.
Agreed. Choppers are good platforms for observation but large turning circle at speed may make them less suited to pursuit.
|
'Out run" may not be the best description, but I've heard of a handful cases over the years where a fast car has managed to evade the gaze of the chopper.
The chopper's range may come into it, and presumably it cannot always fly exactly where the pilot would like due to air traffic control.
For this story, the proof of the pudding may be in the eating.
On their own account, it took the coppers several goes to catch this git and I imagine the chopper would have been up for several of the earlier tries.
|
>> Agreed. Choppers are good platforms for observation but large turning circle at speed may make
>> them less suited to pursuit.
>>
Except they don't need to turn quickly. It doesn't need to replicate every twist and turn made by the vehicle being pursued, just head in vaguely the same direction and keep it in sight.
|
>> Except they don't need to turn quickly. It doesn't need to replicate every twist and
>> turn made by the vehicle being pursued, just head in vaguely the same direction and
>> keep it in sight.
Exactly
|
>> What a load of hogwash.
So this Audi RS5 (one of only two in the country....) was a saloon. That does make it a fairly unique RS5 in my opinion. And it was so fast you could stop to rob some places before the policy could catch up.
And this RS5 had the V10 Lambo derived engine from the RS6 and R8... so I guess it was a special RS5 ;-)
Last edited by: rtj70 on Wed 15 Aug 12 at 22:01
|
A number of factors are involved in limiting the top speed of helicopters..... a simple explanation here......
www.helis.com/howflies/maxspeed.php
|
I've no aerodynamics training, but I've wondered before about the retreating blade in forward flight. Does it really stall? I understand stall (in a fixed wing) to be when the pitch is too great. As airflow reversal velocity (a new phrase to me, trips off the tongue a treat) is approached wouldn't the section of blade effectively be in still air?
Do rotor tips ever approach supersonic velocity in fast flight? A whole new can of worms!
|
>> www.helis.com/howflies/maxspeed.php
>>
>>
>>
>> Load of bull
"Stall is a condition where there is a breakdown of smooth laminar airflow over the surfaces of an aerofoil (rotor blade)."
There is rarely totally laminar flow over any aerofoil and my understanding of stall is where the airspeed of a wing is too slow to create lift, oddly when airspeed is low the flow is MORE likely to be laminar.
Not read any further.
Yes rotor speed limits travel speed but if he was correct they would not be nose up but leaning one way, of course to move forwards you tilt the whole rotor and lift the helicopter as it were, the disc is not horizontal except in a hover.
|
As airspeed increases, the advancing blade on the right side of the helicopter produces more lift. Likewise, on the left side of the helicopter, due to the increase in speed, the retreating blade produces less lift because it is travelling in the opposite direction of the helicopter. Multi-bladed helicopters have a flapping hinge, while 2 bladed helicopters have a teetering hinge which allows the rotor blades to flap to compensate for this lift differential that occurs.
As the airspeed increases, lift increases, and the blade flaps up on the advancing side, which in turn decreases the angle of attack of the blade, and lift is reduced. On the retreating side, the blade flaps down which increases the angle of attack on that blade, and through this flapping action, lift is equalized across the rotor disk. There is a point, which varies from one helicopter to another, where this flapping action can no longer over come the imbalance of lift across the rotor disk, and the retreating blade will stall.
|
They said all this about the lotus carlton in the 90s.
He was lucky some MLH didn't bimble out in front of him at that speed. Apart from anything most motorways have CCTV along them and many of the overhead gantries will have specs so it would be rather easy to keep track of where he was even if the helicopter wasn't actually anywhere near him.
It's the usual journalistic exaggeration.
|
>> Apart from anything most motorways have CCTV along them and many of the overhead gantries
>> will have specs so it would be rather easy to keep track of where he
The specs cannot be viewed in fast time.
|
Jailed for 9 years: www.bbc.co.uk/news/uk-england-19347144
"In footage recorded from the police helicopter during the incident, sparks were seen coming from underneath the car because of the speed at which it was going."
Eh? Downforce?
|
"A man caught doing 180mph in a police chase on the M6 in the West Midlands has been jailed for nine years."
I really really get annoyed by the BBCs editors for this - and they do it all the time. The implication is, and is intended to be, that he was jailed for speeding.
He was not. He was found guilty of conspiracy to burgle, conspiracy to steal and dangerous driving at an earlier trial.
But that's just the sort of sensationalism that the BBC adores. And the level in inaccurate and misleading reporting it specialises in.
|
>> He was not. He was found guilty of conspiracy to burgle, conspiracy to steal and
>> dangerous driving at an earlier trial.
The BBC1 news just reported that it was 1.5 years for dangerous driving and 7.5 years for the other stuff.
|
and nothing for speeding.
They do this all the time; their headline was factually correct, but intended to sensationalise and mislead.
|
>> "In footage recorded from the police helicopter during the incident, sparks were seen coming from underneath the car because of the speed at which it was going."
>>
>> Eh? Downforce?
Nope, grouning as opposed to ground effect.
The audi would be very low-slung by design, and hitting a bump/pothole, would cause the car to bottom-out, and whack the exhaust on the road.
i've done it occasionally whilst being 'enthusiastic' in a sporty car.
|
|
Mmm... just watched the BBC video and the 'sparks' appear to be continuous (ffwd to about 1:00), so I'm surprised if it's due to road irregularities given it's on a motorway.
Last edited by: Focus on Thu 23 Aug 12 at 15:51
|
|
Actually, as it's infra-red, is it just hot exhaust rather than flames/sparks?
|
Or his antics have caused the exhaust or some other underbody stuff to come loose and get dragged along?
|
|
Yeah, could have gone over a speed hump or something.
|
|
...although I favour the hot exhaust explanation - it looks like the trails stop briefly when I reckon he's changing gear.
|
Or a pothole!
But at those sort of speeds, and on a hard suspension, things can break easily.
I drove a renault gordini and a similarly-tweaked Fiesta while back - lovely little cars, but I couldn't live with them - eveypebble, it seemed, send shockwaves through the bodywork! My poor aching back!
|
Audi RS6 V10 - Policeneed faster helicopter - Westpig
