RE: Axe finally falls on Bloodhound SSC project
Discussion
14 said:
Because then they wouldn’t be able to break the World Land Speed record, which is what Bloodhound SSC is all about.
As I said, that's one of the absurdities of the current rules. It wouldn't take much to change those rules, to allow a standard, human-sized dummy pilot.The other very pertinent question is whether it actually is what Bloodhound SSC
Is it about breaking the WLSR (which could have been done much more cheaply if they'd been less ambitious about their target speed), achieving 1,000mph on land (already done by rocket sleds), promoting UK technology (using a Scandinavian engine) or inspiring STEM subject education in children (with a project that is counter to the green, anti-climate change ethos that is being pushed in every other field of science and engineering at the moment)?
There are a long list of reasons why the project was irrelevant and should have failed, and - so far as I can see - only the mountaineer's old chestnut 'because it's there' as a reason to pursue it.
Equus said:
14 said:
Because then they wouldn’t be able to break the World Land Speed record, which is what Bloodhound SSC is all about.
As I said, that's one of the absurdities of the current rules. It wouldn't take much to change those rules, to allow a standard, human-sized dummy pilot.The other very pertinent question is whether it actually is what Bloodhound SSC
Is it about breaking the WLSR (which could have been done much more cheaply if they'd been less ambitious about their target speed), achieving 1,000mph on land (already done by rocket sleds), promoting UK technology (using a Scandinavian engine) or inspiring STEM subject education in children (with a project that is counter to the green, anti-climate change ethos that is being pushed in every other field of science and engineering at the moment)?
There are a long list of reasons why the project was irrelevant and should have failed, and - so far as I can see - only the mountaineer's old chestnut 'because it's there' as a reason to pursue it.
Any way, just prior to Newquay 2017 one of the marketeers said in a meeting "why don't we replace the V8 with an electric motor", he was saluted as a hero with a bloody great idea.......
IN51GHT said:
One of my arguments with the project leaders from an early stage of my involvement was "why using an engine for the H2O2 pump, why not an electric motor as it was more appropriate technology.
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
Equus said:
IN51GHT said:
One of my arguments with the project leaders from an early stage of my involvement was "why using an engine for the H2O2 pump, why not an electric motor as it was more appropriate technology.
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
Regarding the rockets performance, i'm not sure for this application, which is a "very slow" speed device (compared to an orbital rocket system) that specific impulse makes much difference. What matters is max thrust, and that is more likely to be a function of the basic architecture of the rocket and fuel burn rate. For example, the solid boosters on the Space Shuttle only achieved a sea level SI of around 230, yet each one pushes out 11.5 MN of thrust!
Max_Torque said:
...i'm not sure for this application...that specific impulse makes much difference. What matters is max thrust, and that is more likely to be a function of the basic architecture of the rocket and fuel burn rate.
Specific impulse is simply a measure of how much thrust you get for every kg of propellant 'burned', so it matters very much.If your propellant gives a lower specific impulse, you need to carry and burn more of it to generate the same level of thrust, hence you have more mass to accelerate in the early part of the run (and you need a bigger, heavier structure to carry it).
Obviously, the major disadvantage of rockets is that their fuel load is a very significant proportion of their overall weight (and on LSR vehicles is critical - ask Walt Arfons and Stan Barrett
), so anything you can do to reduce that disadvantage is equally critical.Edited by Equus on Tuesday 11th December 12:05
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
p1stonhead said:
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
A single typical large (1.5m tall x 0.23m dia) nitrogen cylinder is 9.8m^3 at 230 bar at 25degC, the equivalent of 2.89m^3 at 1000 psi. it weighs 85 kg when full.
There, job done. Hardly a problem it would seem (way lighter than any other solution even with an off-the-shelf steel cylinder) and costs just £35 in singles from BOC........
Equus said:
Max_Torque said:
Specific impulse is simply a measure of how much thrust you get for every kg of propellant 'burned', so it matters very much.
For a rocket, which has to lift it's own mass into space sure, but for a car, i think not. A 10% reduction in SI means a 10% heavier rocket, a bummer if you're trying to get a satellite into earth orbit (22,000 miles up and travelling 7,000 mph (ish)) but not a problem on a car that has to travel a few miles at "just" 1000 mph..... What does the Nammo rocket weigh, lets say a tonne, well, that means a 100kg penalty. Nothing to worry about......Max_Torque said:
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
A single typical large (1.5m tall x 0.23m dia) nitrogen cylinder is 9.8m^3 at 230 bar at 25degC, the equivalent of 2.89m^3 at 1000 psi. it weighs 85 kg when full.
There, job done. Hardly a problem it would seem (way lighter than any other solution even with an off-the-shelf steel cylinder) and costs just £35 in singles from BOC........
t, why didn't we think of that!!!!!!IN51GHT said:
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank.
What was the burn time on the motor? Blue Flame managed it, of course, and was designed for not far off Bloodhound's level of rocket thrust (100kN instead of 122kN), with a burn time of 20 seconds.
The whole Blue Flame programme went from initial design concept to record in little more than 2 years, and the basic design - including rocket motor - was handled by 3 guys, on drawing boards, with slide rules. We do seem to have a habit of making our speed record designs vastly more complicated and expensive than they need to be, in this country...
Edited by Equus on Tuesday 11th December 13:41
Equus said:
IN51GHT said:
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank.
What was the burn time on the motor? Blue Flame managed it, of course, and was designed for not far off Bloodhound's level of rocket thrust (100kN instead of 122kN), with a burn time of 20 seconds.
They whole Blue Flame programme went from initial design concept to record in little more than 2 years, and the basic design - including rocket motor - was handled by 3 guys, on drawing boards, with slide rules. We do seem to have a habit of making our speed record designs vastly more complicated and expensive than they need to be, in this country...
Daston said:
I think their marketing is pretty poor, would be interested to see how much they could raise via Kickstarter. Seeing that a computer game made $200,000,000
They had several, eg:https://www.indiegogo.com/projects/bloodhound-supe...
and
https://www.crowdfunder.co.uk/bloodhound
Remember XH558 had a much wider appeal and it took a long time to get a fraction.
(Actually that reminds me, I pledged £10 for a Bloodhound skin pin and I'm not sure I ever received it... it might be buried under crap somewhere though)
Edited by Gareth79 on Tuesday 11th December 13:57
IN51GHT said:
Max_Torque said:
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
A single typical large (1.5m tall x 0.23m dia) nitrogen cylinder is 9.8m^3 at 230 bar at 25degC, the equivalent of 2.89m^3 at 1000 psi. it weighs 85 kg when full.
There, job done. Hardly a problem it would seem (way lighter than any other solution even with an off-the-shelf steel cylinder) and costs just £35 in singles from BOC........
t, why didn't we think of that!!!!!!"One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need"
is not a valid engineering concern as the demonstrated.
Max_Torque said:
IN51GHT said:
Max_Torque said:
IN51GHT said:
Equus said:
Given that the rocket was a 'booster' to the jet engine, did it actually need a fuel pump at all? Why not just use pressurised nitrogen, as cars like Blue Flame had done - or was the burn time/fuel volume required deemed to be too great?
I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need to have onboard to maintain a constant 1000psi in the H2O2 tank. I'm also curious about the decision to use polybutadiene as a solid propellant. The project website quotes a specfic impulse of 200 seconds, which is barely better than a well-designed HTP only rocket (I think NASA quotes a specific impulse of 150 for HTP, but that seems conservative - perhaps because they tend to use it for small rockets for attitude adjustment - I know others who confidently claim up to 190 for HTP). I think the DeHavilland Spectre that my friend designed was achieving a specific impulse of 265, on HTP and Kerosene, so 30-odd% better than Bloodhound was claiming, back in the 1950's?
A single typical large (1.5m tall x 0.23m dia) nitrogen cylinder is 9.8m^3 at 230 bar at 25degC, the equivalent of 2.89m^3 at 1000 psi. it weighs 85 kg when full.
There, job done. Hardly a problem it would seem (way lighter than any other solution even with an off-the-shelf steel cylinder) and costs just £35 in singles from BOC........
t, why didn't we think of that!!!!!!"One of the problems with a 1000litre H2O2 @ 1000psi blowdown system is the amount of Nitrogen you'd need"
is not a valid engineering concern as the demonstrated.
slipstream 1985 said:
Bit of a dead end development and tech wise. What advantages will come from it? I know we should always be pushing technical bondaries but land based high speeds are not the way forward. Maglev trains, vacuum tunnels and space travel are the way forward for high speed transport.
I think the telling stat is:1963 - 407 mph
1965 - 600 mph
1970 - 622 mph
1983 - 633 mph
1997 - 760 mph
The last two were driven forward by the same bloke, so essentially the last time someone other than Richard Noble credibly wanted to break the LSR was 1970!
The record breaking in the 1960's was all tied up in the jet/space age and hot rodding, the Beach Boys even sang about Spirit of America. Thrust 2 was achieved for not that much money so the "for Britain and for the hell of it" passed as an acceptable reason, SSC had the sound barrier and and cool Britannia and the new concept of having a website behind it.
Today with global warming, SpaceX, social consciousness and electric cars being the zeitgeist the idea of using a rocket and a jet to go at 1000 mph is a bit old hat and somewhat lacking in spectacle when you can watch the onboard camera of a space rocket live on Youtube.
Hundreds of teams applied to test their pods in the SpaceX vacuum tube and the world's media turned up to see them go not that fast.
I suspect the only way to get some real money behind the LSR would be if you planned to crack it with an electric car, even then I suspect it would probably be the makes behind on electric cars who would sponsor it.
The 60's efforts were also heavily funded by either Goodyear and Firestone, and a few other companies and used as marketing, hence why the available footage is all very good to be honest.
What people ought to remember is that Arfons was pushing 600+mph in the early days in his battle with Craig, could have almost put it beyond reach even of Thrust 2 if he had not been such a throttle jockey! Spirit 2 was nearly taking off at 600+ and bodywork breaking etc, so he got out when he broke 600!
AS if you read Richards book, that Avon was at its limit, as was the car to go 633.
They even considering pushing SSC further too, but decided against it.
Breedlove in fact bought a rocket motor, and was considering it, until the fuel costs got insane, Blue Flame was funded by the gas industry to get around that in some way, but is by far and away the most perfect and beautiful LSR car even made in my eyes.
Should I mention the Budweiser Rocket...
What people ought to remember is that Arfons was pushing 600+mph in the early days in his battle with Craig, could have almost put it beyond reach even of Thrust 2 if he had not been such a throttle jockey! Spirit 2 was nearly taking off at 600+ and bodywork breaking etc, so he got out when he broke 600!
AS if you read Richards book, that Avon was at its limit, as was the car to go 633.
They even considering pushing SSC further too, but decided against it.
Breedlove in fact bought a rocket motor, and was considering it, until the fuel costs got insane, Blue Flame was funded by the gas industry to get around that in some way, but is by far and away the most perfect and beautiful LSR car even made in my eyes.
Should I mention the Budweiser Rocket...
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