RE: 'Desert spec' Bloodhound LSR revealed

RE: 'Desert spec' Bloodhound LSR revealed

Tuesday 29th October

Bloodhound hits fastest ever speed | LSR Update

Britain's land speed challenger begins to stretch its legs...



Having overcome its initial teething problems and sailed through a 100mph test run, the Bloodhound LSR test programme has begun to pick up pace. Having set its previous top speed of 200mph during its 2017 trials at Newquay airport, the car took advantage of the rather more expansive surroundings of the Hakskeen Pan to open the taps a little further.Β 

Two initial 100mph and 200mph β€˜run profiles’ were completed before the Eurofighter EJ200 jet engine was run on full reheat - that’s afterburner to you and me - propelling the car right up to 334mph in just 12 seconds. That’s quick however you look at it, but is just a third of the eventual 1,000mph top speed that the Bloodhound team is aiming to hit.Β 

That third run marks the start of the true high-speed test schedule and allowed the team to gather crucial wind speed data while conducting all the necessary checks to continue ramping things up. The car’s speed will now be increased in 50mph increments in each subsequent run profile over the next four weeks, with a target in excess of 500mph being the goal.Β 

Β 

Speaking of the day’s progress, driver Andy Green said: β€œWe’ve had two very successful runs today, with the second run reaching a max speed of 334mph – going from 50mph to 300mph in 13 seconds. There was strong cross wind gusting at over 15mph and we’ve established that this is pretty much the limit for running in the car. We’re happy because this was a successful test, now we’re ready to progress on to higher speeds.”

A full breakdown of the runs so far is as follows:Β 

Run Profile 1 – a static engine test, followed by a very slow speed (max 100 mph) check of the steering and brakes.

Run Profile 2 – 200 mph achieved using max dry power (power without extra fuel for reheat) on the jet engine, then a coast-down to establish rolling resistance.

Run Profile 3 – 350 mph achieved using full reheat, with stability tests before and after peak speed, then a coast-down period after engine shutdown to measure rolling resistance without idle thrust from the jet engine. Parachute data collected.



28.10.2019

As ever, things haven't gone exactly to plan in South Africa (earlier videos reveal the not entirely unpredictable problems the team has had with its borrowed Eurofighter jet engine) but the latest 'Day 9' footage provides many reasons to be cheerful.

Most notably, of course, the chocks have come off - and just to see Bloodhound in motion over a desert landscape is heartening when you consider how close it came to the scrap heap this year. This new video shows the car completing 'Run Profile One', which apparently involved a static engine test (the one which it failed previously) and a very slow run to check the steering and brakes.

This being LSR, the 'very slow speed' means zipping it straight up to 100mph. Cue some stirring music and the dulcet tones of Andy Green, who reported himself as pleased as punch afterwards. "The car was ready, everything was really slick; it was like (the team) had been doing it for months and months despite the fact that this was our first ever run. Everything worked really well and once we'd got the car rolling, the steering, brakes, engine worked fantastically - this feels like a race car ready to go faster. Next few days we're going to be ramping the speed up quite quickly; the car is ready to go."


21.10.19

It's safe to say that Bloodhound's journey to the Hakskeenpan desert has been considerably longer than the 12 or so hours it must've taken to fly the land speed record challenger to the Northern Cape. The car has suffered so many false starts and near-miss perils that we wondered if we'd ever see it blasting across a billiard table-smooth piece of Mother Nature. And yet here it is, wearing its precision-machined solid aluminium wheels for the first time, and ready to roll.

Of course, as we've previously discussed, Bloodhound's arrival in South Africa does not signal an immediate record attempt, but rather an additional stage in the car's painstaking preparation. Somewhat ironically, one of the key objectives of the LSR's test programme is to study how it behaves when slowing down. The team says it needs to understand better the 'drag and stopping ability' of the jet-powered machine before it can safely run beyond 500mph.


Consequently, the car will be examined under a number of scenarios and at different speeds using the full variety of wheel brakes, drag parachutes and giant airbrakes to see how reality matches up to the existing computational fluid dynamic models. Only when the team is happy with the outcome will it let Andy Green build to higher speeds at 50mph increments.

Mark Chapman, Bloodhound LSR Engineering Director, said: "Newquay was all about getting up to speed and finding out how quickly we could get the engine to full power and accelerate using max reheat. Andy was on the throttle for two seconds to reach 200 mph in eight seconds. Here at the Hakskeenpan on a 10-mile track we can accelerate for much longer, achieve higher speeds and investigate the car's stability, performance and drag, all crucial as we move towards setting a new world land speed record."

It was no mean feat creating that 10-mile track either. Mother Nature provided the flat surface, but the team needed the help of the Northern Cape Provincial Government and members of the local Mier community to clear 16,500 tonnes of rock from 22 million square metres of dry lakebed to ensure that Bloodhound could run unimpeded. For the record, the LSR team reckon it's the largest area of land ever cleared by hand for a motorsport event.


If that weren't impressive enough, the desert has been littered with remote, micro-climate weather stations which record wind speed, gust speed, wind direction, temperature, humidity and barometric pressure, and transmit the data back to the Bloodhound engineers via a low power, long range radio network. The team describe this as some of the most cutting edge technology employed in the project - and with good reason, as a spokesperson for Digital Catapult, the company responsible, explained.

"The car is aiming to go faster than any other land-based machine built thus far. At the speeds hoped for, unexpected cross wind could significantly affect the stability and direction of the vehicle and are therefore a key decision point on when to run the car. We will be measuring and storing accurate data at 1 km points along the track and therefore this info can be used by the team to plan the run."


Read about PH's visit to Bloodhound here






Author
Discussion

Augustus Windsock

Original Poster:

1,822 posts

102 months

Monday 21st October
quotequote all
Sincerely hope they achieve their objective, I really do, but the pessimist in me can’t see it.
Costs and the level of engineering are against it.
Having said that, if the record attempting run was on PPV, I’d definitely pay to see it.
Not quite up there with the first time I saw Concorde, Apollo, or Felix Baumgartner jump, but it will be something to behold if they do get that far.
As an aside, just how many revolutions per second will those wheels have to turn at to reach the speed they are hoping for?

Edited by Augustus Windsock on Monday 21st October 15:24

ChocolateFrog

6,478 posts

120 months

Monday 21st October
quotequote all
Wonder how close it was to actually being chopped up? That would have been a travesty.

Can't see why they won't achieve the aim, breaking LSRs isn't supposed to be easy and it's not like the challenge is getting any easier.

simon-tigjs

46 posts

44 months

Monday 21st October
quotequote all
A fascinating project At 500 mph they are doing 8.3 miles per minute and this is only ten miles long. If they can reach 200mph in 8 secs which is what you suggest, then could possibly reach 500 mph in 20 secs, leaving a comfortable 40 seconds to brake and come to a standstill allowing for a bit of error. Only its well known that acceleration gets harder the faster you go and the amount of effort and energy needed multiplies at an alarming rate, thus time required to get there . I wish them well but they might just need a bigger playing field. Amazing bravery against all the odds.

NJ72

165 posts

45 months

Monday 21st October
quotequote all
Augustus Windsock said:
As an aside, just how many revolutions per second will those wheels have to turn at to reach the speed they are hoping for?
According to Wikipedia (I know, it's what Google threw at me) the below is the case:

Wikipedia said:
The four 36-inch (910 mm) diameter wheels would rotate at up to 10,200 rpm and be forged from an aluminium zinc alloy to resist the 50000 g centrifugal forces.

ChocolateFrog

6,478 posts

120 months

Monday 21st October
quotequote all
simon-tigjs said:
A fascinating project At 500 mph they are doing 8.3 miles per minute and this is only ten miles long. If they can reach 200mph in 8 secs which is what you suggest, then could possibly reach 500 mph in 20 secs, leaving a comfortable 40 seconds to brake and come to a standstill allowing for a bit of error. Only its well known that acceleration gets harder the faster you go and the amount of effort and energy needed multiplies at an alarming rate, thus time required to get there . I wish them well but they might just need a bigger playing field. Amazing bravery against all the odds.
The design speed is 1050mph at the same location so if they're struggling to git 500mph runs in they've got a problem.

EdT

4,867 posts

231 months

Monday 21st October
quotequote all
If this goes on much longer Hennessy might get there first!

Watchman

5,578 posts

192 months

Monday 21st October
quotequote all
article said:
Andy was on the throttle for two seconds to reach 200 mph in eight seconds
How does that work? If you're on the throttle for two seconds you're only accelerating for two seconds, aren't you?

RumbleOfThunder

2,933 posts

150 months

Monday 21st October
quotequote all
simon-tigjs said:
A fascinating project At 500 mph they are doing 8.3 miles per minute and this is only ten miles long. If they can reach 200mph in 8 secs which is what you suggest, then could possibly reach 500 mph in 20 secs, leaving a comfortable 40 seconds to brake and come to a standstill allowing for a bit of error. Only its well known that acceleration gets harder the faster you go and the amount of effort and energy needed multiplies at an alarming rate, thus time required to get there . I wish them well but they might just need a bigger playing field. Amazing bravery against all the odds.
The full on record runs will use the addition of a hybrid rocket to get up to higher speeds. At this point only jet power is needed.

oilit

827 posts

125 months

Monday 21st October
quotequote all
in many ways this is a fingers and toes crossed and other parts of ones anatomy clenched moment laugh

I wish them the best of luck

Edited by oilit on Monday 21st October 18:25

simon-tigjs

46 posts

44 months

Monday 21st October
quotequote all
The design speed is 1050mph at the same location so if they're struggling to git 500mph runs in they've got a problem.

I was trying to work out how far down the run they would be at 500mph but then read your comment. 1050 mph ??? as in 17.5 miles per minute or 34 seconds at maximum velocity to clear the course. Add in terminal velocity to push through at circa 200mph even allowing for zero wind and the air doesn't get thinner like a rocket climbing, the sound barrier at circa 700mph, the fact the ground speed is not diluted like a jet fighter 200 feet off the ground, it might be a tad bumpy and a breath of wind is likely to be devastating to its stability, one does wonder if there has been a touch too much Michael Gove consumed on this project. It would be a staggering achievement. Go boys. Go !

Name of user

173 posts

54 months

Monday 21st October
quotequote all
Watchman said:
How does that work? If you're on the throttle for two seconds you're only accelerating for two seconds, aren't you?
Because it’s a jet engine, it is still providing (a lot) of thrust on the overrun!

Sandpit Steve

328 posts

21 months

Monday 21st October
quotequote all
Great job to get it this far, after all the setbacks. Best of luck to all the guys and gals involved in the running, especially Andy Green in the hot seat!

gary58

208 posts

78 months

Monday 21st October
quotequote all
Who pays for this

It was no mean feat creating that 10-mile track either. Mother Nature provided the flat surface, but the team needed the help of the Northern Cape Provincial Government and members of the local Mier community to clear 16,500 tonnes of rock from 22 million square metres of dry lakebed to ensure that Bloodhound could run unimpeded. For the record, the LSR team reckon it's the largest area of land ever cleared by hand for a motorsport event.

oilit

827 posts

125 months

Monday 21st October
quotequote all
Maybe viewing rights for volunteers or local workers who regrettably aren't paid very much

ChocolateFrog

6,478 posts

120 months

Monday 21st October
quotequote all
Watchman said:
article said:
Andy was on the throttle for two seconds to reach 200 mph in eight seconds
How does that work? If you're on the throttle for two seconds you're only accelerating for two seconds, aren't you?
No you're still accelerating but at a decreasing rate.

williamp

16,649 posts

220 months

Monday 21st October
quotequote all
ChocolateFrog said:
Watchman said:
article said:
Andy was on the throttle for two seconds to reach 200 mph in eight seconds
How does that work? If you're on the throttle for two seconds you're only accelerating for two seconds, aren't you?
No you're still accelerating but at a decreasing rate.
..plus, tl avoid the vacuum sucking in dirt, he started to accelerate very slowly, gradually building up speed, and only then going full throttle

Zad

11,910 posts

183 months

Tuesday 22nd October
quotequote all
A (currently) 166 page active thread running here: https://www.pistonheads.com/gassing/topic.asp?h=0&...

Including quite a few postings from people directly involved in the project.

Augustus Windsock

Original Poster:

1,822 posts

102 months

Tuesday 22nd October
quotequote all
ChocolateFrog said:
No you're still accelerating but at a decreasing rate.
It’s nearly 40years since I did physics ‘O’ level but if you are not accelerating, or staying at a constant speed, are you not actually decelerating (even if not actively, by applying brakes, deploying a parachute etc)?
I’m getting old and puddled, and I’m definitely no Stephen Hawking, so I may be totally wrong of course!

Mules

60 posts

94 months

Tuesday 22nd October
quotequote all
Watchman said:
How does that work? If you're on the throttle for two seconds you're only accelerating for two seconds, aren't you?
A jet engine continues to produce power when you lift off the throttle as the turbine is still spinning.


Mules

60 posts

94 months

Tuesday 22nd October
quotequote all
ChocolateFrog said:
simon-tigjs said:
A fascinating project At 500 mph they are doing 8.3 miles per minute and this is only ten miles long. If they can reach 200mph in 8 secs which is what you suggest, then could possibly reach 500 mph in 20 secs, leaving a comfortable 40 seconds to brake and come to a standstill allowing for a bit of error. Only its well known that acceleration gets harder the faster you go and the amount of effort and energy needed multiplies at an alarming rate, thus time required to get there . I wish them well but they might just need a bigger playing field. Amazing bravery against all the odds.
The design speed is 1050mph at the same location so if they're struggling to git 500mph runs in they've got a problem.
We've got 16km of desert to work with this year, that's ample to reach speeds north of 500mph and stop safely. At max reheat the car will accelerate at 40mph per second.