Good question Channi – the answer is a jet engine and a lot if you are standing right behind it!
The EJ200 is a military turbofan engine that we shall be using to get our car up to 300mph (before the rocket kicks in). It is normally found however in the engine bay of a Eurofighter Typhoon. You may have seen this plane (if not, perhaps search on Google?) on Top Gear when it raced the Bugatti Veyron.
As for how it will effect the driver of our vehicle, it will accelerate him from 0 to 300mph in just 22 seconds, then he will accelerate to 1000mph in a further 20 seconds, pushing a force of 3G on his body… that’s the same as 3 of the force of gravity on you (imagine lying on the floor with 3 of you pushing on your chest). He will then turn off the EJ200 and decelerate back to 0… and in that time will have covered ten and a half miles…
I love a good calculation … can’t help pointing out that 300 to 1000mph in 20s is a change in velocity of 700mph in 20s, which gives an average acceleration of:
700mph/20s = 700mile/hour * 1609 m/mile *(1hour/60min)(1min/60s) /20s = 15.6 m/s/s. So, with g=9.8 m/s/s this looks like an average acceleration of 15.6/9.8 or about 1.6G. So is 3G the peak acceleration?
I love someone who can look deeper into the figures!
Yes Keith, the 3G is at peak acceleration. The acceleration changes dramatically after the 22 seconds when the rocket kicks in. The main issue is not so much with the peak G though, but with the swapover between positive and negative G when we go from acceleration to deceleration.
If you fancy having a look at our run profile, you can find it here http://www.bloodhoundssc.com/adventure/the_record_run.cfm 🙂
Comments
channi commented on :
cool that sounds great !! 🙂
Keith commented on :
I love a good calculation … can’t help pointing out that 300 to 1000mph in 20s is a change in velocity of 700mph in 20s, which gives an average acceleration of:
700mph/20s = 700mile/hour * 1609 m/mile *(1hour/60min)(1min/60s) /20s = 15.6 m/s/s. So, with g=9.8 m/s/s this looks like an average acceleration of 15.6/9.8 or about 1.6G. So is 3G the peak acceleration?
Hywel commented on :
I love someone who can look deeper into the figures!
Yes Keith, the 3G is at peak acceleration. The acceleration changes dramatically after the 22 seconds when the rocket kicks in. The main issue is not so much with the peak G though, but with the swapover between positive and negative G when we go from acceleration to deceleration.
If you fancy having a look at our run profile, you can find it here http://www.bloodhoundssc.com/adventure/the_record_run.cfm 🙂
channi commented on :
that is alot to comment on lol but there is a lot of information 2 read and it took me ages to read it 🙂