Bloodhound LSR Thread As Requested...

Bloodhound LSR Thread As Requested...

Author
Discussion

Storer

5,024 posts

215 months

Wednesday 23rd July 2014
quotequote all
El Guapo said:
IN51GHT said:
Here's (left to right) Roland (Stress) Tufty (build tech) & myself (snr engineer) going through the final snagging list before the uppers chassis comes apart for bond prep'

Are you triplets?
I could be the fourth brother. Glasses, greying hair surrounding a sun tanned knowledge enclosure (technical term!) and I wear shorts from May to October, even to see my accountant tomorrow morning. Also safety sandals, even in the rain.
I am obviously the dumber brother (probably the youngest, so the genes were getting exhausted) but I could wear the shirt (XL in my case)....

On a serious note!
Went to Pendine Sands last week and had a look at Babs. Any LRS breaker has big respect but to do 171mph in that very simple car on wet sand with no safety equipment shows the "no fear" spirit.
I found it quite ironic that what I am building will have more cu in, power, torque, etc. but there is no way I want to see north of 100mph in something designed in 1935 and built in 1937. I don't have that "no fear" spirit!


Paul

IN51GHT

Original Poster:

8,777 posts

210 months

Thursday 24th July 2014
quotequote all
lufbramatt said:
Is Conor Lagrue to same one that was associated with Race Shack? Remember the name from the Beetle Crisis series on TV smile
Correct.

IN51GHT

Original Poster:

8,777 posts

210 months

Thursday 24th July 2014
quotequote all
Storer said:
I could be the fourth brother. Glasses, greying hair surrounding a sun tanned knowledge enclosure (technical term!) and I wear shorts from May to October, even to see my accountant tomorrow morning. Also safety sandals, even in the rain.
I am obviously the dumber brother (probably the youngest, so the genes were getting exhausted) but I could wear the shirt (XL in my case)....

On a serious note!
Went to Pendine Sands last week and had a look at Babs. Any LRS breaker has big respect but to do 171mph in that very simple car on wet sand with no safety equipment shows the "no fear" spirit.
I found it quite ironic that what I am building will have more cu in, power, torque, etc. but there is no way I want to see north of 100mph in something designed in 1935 and built in 1937. I don't have that "no fear" spirit!


Paul
Was Babs running? She sounds simply awesome.

Megaflow

9,386 posts

225 months

Thursday 24th July 2014
quotequote all
IN51GHT said:
lufbramatt said:
Is Conor Lagrue to same one that was associated with Race Shack? Remember the name from the Beetle Crisis series on TV smile
Correct.
I did wonder. What happened to Race Shack?

IN51GHT

Original Poster:

8,777 posts

210 months

Thursday 24th July 2014
quotequote all
Megaflow said:
IN51GHT said:
lufbramatt said:
Is Conor Lagrue to same one that was associated with Race Shack? Remember the name from the Beetle Crisis series on TV smile
Correct.
I did wonder. What happened to Race Shack?
I've no idea to be honest.

Storer

5,024 posts

215 months

Thursday 24th July 2014
quotequote all
IN51GHT said:
Storer said:
I could be the fourth brother. Glasses, greying hair surrounding a sun tanned knowledge enclosure (technical term!) and I wear shorts from May to October, even to see my accountant tomorrow morning. Also safety sandals, even in the rain.
I am obviously the dumber brother (probably the youngest, so the genes were getting exhausted) but I could wear the shirt (XL in my case)....

On a serious note!
Went to Pendine Sands last week and had a look at Babs. Any LRS breaker has big respect but to do 171mph in that very simple car on wet sand with no safety equipment shows the "no fear" spirit.
I found it quite ironic that what I am building will have more cu in, power, torque, etc. but there is no way I want to see north of 100mph in something designed in 1935 and built in 1937. I don't have that "no fear" spirit!


Paul
Was Babs running? She sounds simply awesome.
No, sat in the little museum but still looked loud.

Also a little terrifying! Probably fine up to about 70mph but I can't imagine adding another 100+ to that figure.


Paul

Silent1

19,761 posts

235 months

Friday 25th July 2014
quotequote all
IN51GHT said:
Megaflow said:
IN51GHT said:
lufbramatt said:
Is Conor Lagrue to same one that was associated with Race Shack? Remember the name from the Beetle Crisis series on TV smile
Correct.
I did wonder. What happened to Race Shack?
I've no idea to be honest.
Google suggests things didn't end well for race shack

IN51GHT

Original Poster:

8,777 posts

210 months

Monday 28th July 2014
quotequote all
Airbrake mechanism bellcranks & pushrods now trial installed.






El Guapo

2,787 posts

190 months

Monday 28th July 2014
quotequote all
The scale of all that is impressive. What speed will SSC be doing when the air brakes are deployed?

IN51GHT

Original Poster:

8,777 posts

210 months

Monday 28th July 2014
quotequote all
El Guapo said:
The scale of all that is impressive. What speed will SSC be doing when the air brakes are deployed?
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.

McWigglebum4th

32,414 posts

204 months

Monday 28th July 2014
quotequote all
That looks seriously beefy to hold a couple of doors open against a bit of a breeze


What kind of force does it take to open the doors fully at 800mph?

IN51GHT

Original Poster:

8,777 posts

210 months

Monday 28th July 2014
quotequote all
McWigglebum4th said:
That looks seriously beefy to hold a couple of doors open against a bit of a breeze


What kind of force does it take to open the doors fully at 800mph?
Roland (head of stress) says 50kN per side

IN51GHT

Original Poster:

8,777 posts

210 months

Monday 28th July 2014
quotequote all
If you are a fan of Bloodhound & K'Nex - http://www.bloodhoundssc.com/KNEX

El Guapo

2,787 posts

190 months

Monday 28th July 2014
quotequote all
IN51GHT said:
El Guapo said:
The scale of all that is impressive. What speed will SSC be doing when the air brakes are deployed?
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.
OK, very interesting. Do you happen to know how many decel g you would get at 800mph with no air brakes? I'm honestly not trying to be a smartarse, it just seems like a lot of additional engineering for a modest return (increasing decel from say 2g to 3g).

IN51GHT

Original Poster:

8,777 posts

210 months

Monday 28th July 2014
quotequote all
El Guapo said:
IN51GHT said:
El Guapo said:
The scale of all that is impressive. What speed will SSC be doing when the air brakes are deployed?
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.
OK, very interesting. Do you happen to know how many decel g you would get at 800mph with no air brakes? I'm honestly not trying to be a smartarse, it just seems like a lot of additional engineering for a modest return (increasing decel from say 2g to 3g).
We get approx 3g from throttle off at 1000mph, at 800mph it somewhere in the region of 2g, we want to maintain as close to 3g as possible, hence the variable angle airbrakes. Don't forget drag squares with speed, so the rate a deceleration would ease the slower the car was traveling if we relied on body drag alone.

Sway

26,254 posts

194 months

Monday 28th July 2014
quotequote all
So how does slowing down work?

Lift off throttle at 1000mph
Air brake automatically deployed at c. 800mph
Parachute?
Disc brakes?

anonymous-user

54 months

Monday 28th July 2014
quotequote all
IN51GHT said:
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.
"line pressure"? As in brake line pressure?

Silent1

19,761 posts

235 months

Monday 28th July 2014
quotequote all
Max_Torque said:
IN51GHT said:
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.
"line pressure"? As in brake line pressure?
Perhaps they're measuring the hydraulic line pressure and using that to adjust the angle and aim for 50kn of force on the air brakes?

Mave

8,208 posts

215 months

Monday 28th July 2014
quotequote all
Silent1 said:
Perhaps they're measuring the hydraulic line pressure and using that to adjust the angle and aim for 50kn of force on the air brakes?
That's how I read it. If you want to achieve a g-level using airplanes, you need constant pressure assuming linear relationships between actuator and airbrake forces.

anonymous-user

54 months

Monday 28th July 2014
quotequote all
Silent1 said:
Max_Torque said:
IN51GHT said:
In the region of 800mph, they will be deployed to maintain a constant 3g deceleration by using a close loop control system with the line pressure as the input.
"line pressure"? As in brake line pressure?
Perhaps they're measuring the hydraulic line pressure and using that to adjust the angle and aim for 50kn of force on the air brakes?
Except the actuating linkage ratio looks to be highly dependent upon actuator position, and so hydraulic pressure will not be linear with drag/deceleration!