Thrust SSC question from another forum

[vx220]

Don't know if anyone can shed any light on this, but did Thrust SSC use some kind of speaker/audio system arrangement for downforce?

I feel a bit daft asking, as it seems unlikely. However, it's not April...

Thanks in advance!

[Rene Souffle]

I always thought it was done by the fact the engines were angled down by a couple of degrees so it couldn’t lift even if it wanted to, that and ground effect.

Edited by Rene Souffle on Tuesday 13th September 21:03

[ChocolateFrog]

vx220 said:

Don't know if anyone can shed any light on this, but did Thrust SSC use some kind of speaker/audio system arrangement for downforce?

I feel a bit daft asking, as it seems unlikely. However, it's not April...

Thanks in advance!

You'd have to explain that one to me.

[Rene Souffle]

How would a speaker/audio system generate downforce?

[toastyhamster]

Rene Souffle said:

I always thought it was done by the fact the engines were angled down by a couple of degrees so it couldn’t lift even if it wanted to, that and ground effect.

Edited by Rene Souffle on Tuesday 13th September 21:03

I thought later computer modelling had put it a few mph away from lifting.

Anyway.

Saw it in Cov Motor Museum a few years ago, awesome thing. Thrust was there as well, which was a bit scarily basic, bigger balls than me.

[buggalugs]

Rene Souffle said:

I always thought it was done by the fact the engines were angled down by a couple of degrees so it couldn’t lift even if it wanted to, that and ground effect.

Edited by Rene Souffle on Tuesday 13th September 21:03

I heard that too. Bit dodgy if you loose thrust at high speed though! There’s a theory that thats what happened to donald campbell.

[wpa1975]

toastyhamster said:

I thought later computer modelling had put it a few mph away from lifting.

Anyway.

Saw it in Cov Motor Museum a few years ago, awesome thing. Thrust was there as well, which was a bit scarily basic, bigger balls than me.

Nope that was Thrust 2, the designer of Thrust SSC made the discovery when carrying our computer simulations on Thrust 2, Thrust SSC had a design speed of 850mph.

Thrust SSC ran active suspension that at higher speeds pushed the noise into the ground also the engines could be throttled at slightly different rates to help keep it straight.

[wpa1975]

This is an excellent read if you can get a copy.

[vx220]

Thanks for replying.

Something was said about using speakers to generate a partial vacuum under the car? I did think it unlikely

Talking of active suspension, didn't BOSE become involved with that at some point (on road cars)?

Maybe that's where the confusion is coming from...

[Shinysideup]

I wonder if Ron Ayres (Aero) Jerry Bliss (Active Suspension) or Glyn Bowsher (Chassis) ever wrote their own books about Thrust SSC?

[CraigyMc]

vx220 said:

Thanks for replying.

Something was said about using speakers to generate a partial vacuum under the car? I did think it unlikely

Talking of active suspension, didn't BOSE become involved with that at some point (on road cars)?

Maybe that's where the confusion is coming from...

The rear wheels on ssc had active suspension to control the pitch of the vehicle overall.
There was also an emergency rocket motor in the nose that was able to stop the vehicle taking off in the event of a failure of the normal pitch system, but it was only tested and never needed on a run.

The story about speakers or audio being a component of the system for pitch control isn't actually that far off as the frequency response of the rear is similar to a bass driver

[Halmyre]

IIRC, according to Noble's book, for the final LSR runs they disabled the active pitch control and set it at a fixed position.

[Truckosaurus]

Halmyre said:

IIRC, according to Noble's book, for the final LSR runs they disabled the active pitch control and set it at a fixed position.

I was just going to mention that, there was a TV documentary that showed them deciding to disable the suspension and some of the team pointing out they'd not tested or modeled that scenario.

[wpa1975]

Truckosaurus said:

Halmyre said:

IIRC, according to Noble's book, for the final LSR runs they disabled the active pitch control and set it at a fixed position.

I was just going to mention that, there was a TV documentary that showed them deciding to disable the suspension and some of the team pointing out they'd not tested or modeled that scenario.

That was the BBC documentary The Mission, from memory they tried it and it did not work so they switched it back on shortly later.

I have actually got it on VHS Video as a box set with a diecast model, never seen it on DVD

[CraigyMc]

Halmyre said:

IIRC, according to Noble's book, for the final LSR runs they disabled the active pitch control and set it at a fixed position.

Was that for Thrust 2, or Thrust SSC?

There are updates on motorsport.com from the era.
https://us.motorsport.com/general/news/lsr-thrusts...
https://us.motorsport.com/general/news/lsr-thrusts...
https://au.motorsport.com/general/news/lsr-thrusts...
https://us.motorsport.com/general/news/lsr-thrusts...

According to https://us.motorsport.com/general/news/lsr-thrusts... they were tuning the suspension to take load off the front wheels towards the end of the program, run 58.

They only did 66 runs in total per http://www.thrustssc.com/Runs_Database/Runs_Databa... (archived version at https://web.archive.org/web/20060617222531/http://... ought to work even if the original site is down).

The runs DB archive has notes from Andy Green, but it doesn't ever mention switching off the active suspension.

It may be that they stopped changing settings/tuning the rear active suspension at the end of the program and that's the reference Noble is making in his book.

[wpa1975]

CraigyMc said:

Halmyre said:

IIRC, according to Noble's book, for the final LSR runs they disabled the active pitch control and set it at a fixed position.

Was that for Thrust 2, or Thrust SSC?

There are updates on motorsport.com from the era.
https://us.motorsport.com/general/news/lsr-thrusts...
https://us.motorsport.com/general/news/lsr-thrusts...
https://au.motorsport.com/general/news/lsr-thrusts...
https://us.motorsport.com/general/news/lsr-thrusts...

According to https://us.motorsport.com/general/news/lsr-thrusts... they were tuning the suspension to take load off the front wheels towards the end of the program, run 58.

They only did 66 runs in total per http://www.thrustssc.com/Runs_Database/Runs_Databa... (archived version at https://web.archive.org/web/20060617222531/http://... ought to work even if the original site is down).

The runs DB archive has notes from Andy Green, but it doesn't ever mention switching off the active suspension.

It may be that they stopped changing settings/tuning the rear active suspension at the end of the program and that's the reference Noble is making in his book.

As I said for all the record runs I am sure it was switched on, from the BBC program they tried it once but it was horrible to drive by all accounts.

[M1C]

One of my earlier memories that really sticks in my mind was going to see Thrust 2 (i presume at the Coventry Motor Museum)

I was quite young but was aware of the new-ish (at the time) record and had seen pictures of it in books etc.

I went into this theatre to watch a video of it (not knowing it was there too) and when the video ended and the curtain started to draw back, i was utterly flabbergasted, it was SO exciting to a...what...i guess i must have been 8 or 9 when it was put there.

I still prefer the look of it to the SSC, too.

[CraigyMc]

wpa1975 said:

As I said for all the record runs I am sure it was switched on, from the BBC program they tried it once but it was horrible to drive by all accounts.

Yep. Posts crossed due to a delay on my side.

[Baldchap]

vx220 said:

Talking of active suspension, didn't BOSE become involved with that at some point (on road cars)?

I remember this. I want to say it was a Lexus project they were involved with...

Can you imagine? They can't even make decent speakers.

[hairykrishna]

[redacted]