It's 1545, and you're sat on the playa opposite Mile 7, leaning against one of the Merlo's huge off-road tyres and typing your second report of the day. Matt, one of the BBC cameramen, is with you as usual - but this time you have been joined by Christophe from Paris-Match and the photographer Alain Ernoult. Conversation is jovial - Christophe is telling jokes in English - not something I'd like to try in French...
After this morning's run when Comp 1 failed for the fourth run in succession, a concerted effort has been made to isolate the fault that is causing the computer to trip out. Electronics experts Robert Atkinson and Steve O'Donnell haven't stopped all day, rebuilding and resoldering the custom-built onboard circuitry. Jerry Bliss has been hard at work also, analysing the data and programs to find the cause. No such problem had been experienced in Jordan, so to establish whether the problem lay in hardware or software, it has been decided to make some runs with the old software of known reliability.
So what is the difference between the Jordan software and that used this morning? The Jordan software runs the active suspension at a fixed setting instead of varying the car's pitch angle by Mach number, has no throttle abort (which shuts down the engines when the abort system fires), and has no active tail abort (which jacks up the rear end to increase downforce on the car). I should explain that the 'abort system' is designed to monitor the 120-plus sensors and fire if it detects a problem - such as an engine thrust imbalance or a structural failure. Andy also has a button on the steering wheel to fire it manually if he needs. Running in the low 600's with that version of the software should not be a problem - we know that the configuration is safe at those speeds.
The next two run profiles have been modified accordingly. Andy will drive to the Air Speed Indicator, not the Machmeter (which is a computed figure), but keeping the speed profiles unchanged from this morning. If Comp 1 fails again, he will deselect the afterburners and continue at military (dry) power: provided speed on the first run exceeds 400mph, useful data will still be obtained as the plan is to deploy the 'short-strop' parachute to establish its behaviour. The aim in any event will be to stop at the assigned finish point at Mile 12, even if Andy has to cruise at a lower speed than planned.
After ThustSSC ran this morning, the rest of the team have been hard at work continuing with track preparations. Both North and South fodding teams have been out clearing the tracks of anything that might damage the wheels or engines, while "Trackmaster" Jack Franck and "Medic 1" Dave Hackett have been out with the Mach 1 Club members painting lines. Spirit of America ran early this afternoon - but with it starting somewhere around Mile 4 and heading north, we saw little more than the rooster tail heading away from us. No speed has been announced as yet.
With Steve, Robert and Jerry progressing well, it was decided to make the next two runs this afternoon, tentatively starting around 1600hrs. A team briefing was held at 1500hrs, before everyone headed out to their assigned positions. The USAC timekeepers were advised, the microlights launched and the security team deployed.
At 1614 Runs Controller Jayne Millington is on the air: "All stations stand by. SSC is still in the compound and is expected to roll out shortly." You type on.
1620 - "All stations stand by. SSC is rolling out." Paul Remfry - callsign "Blackadder", in charge of desert security - calls by to say hello. A white vehicle is spotted at speed on the west side of the playa to the south of you - Paul speeds off to intercept.
1640 - "All stations stand by. Approximately 10 minutes to engine start". One of the microlights 'buzzes' you then swoops low over the tracks en route to the other side of the playa. Jerry Bliss as "Telemetry" advises Jayne that he will be proceeding to SSC as quickly as possible after the run - presumably to find out the result of the test and prepare for a possible second run.
1645- "All stations stand by. Be advised the desert is clear at this point. Emergency transmissions only until SSC has called 'safe'".
At 1653, SSC calls in - the car is armed. You can't hear the SSC - atmospheric conditions have changed since the morning and reception ranges have fallen. Jayne confirms with the USAC timekeepers that they are ready - estimated time to run is five minutes. There is a slight delay and the two minutes to run warning is given just before 1700.
At 1700 Jayne clears Andy to roll and advises all stations. The rooter tail rises behind the car, slowly at first, then with increasing speed. As the sound from the car reaches you the jet-car storms out of the mirage. She is moving fast and continuing to accelerate. Andy levels his speed off using maximum military power (no afterburners) as he approaches the measured mile, and as he clears it he spools down the Speys, deploys the 'chute, and brakes to a stand by Team 2 at Mile 12. He calls stopped - and we hear the acknowledgement from the Pit Station: "Copied. SSC has stopped, computers are still running."
In no time Andy has called 'safe' and "USAC Timing" comes on the air. Dave Petrali reads out three times: kilometre speed was 553.970mph, mile was 553.931, the 1900ft from Mile start to Kilo start was 553.867 - they are staggeringly close.
"That's copied. Thanks!" responds Jayne.
"He had the cruise control on," replies the Chief Steward.
You wonder why the peak speed was not the 600 or so planned. It later transpires that Andy may have left the static line to the Air Speed Indicator open by mistake - causing the gauge to read high, and hence his ground speed to be lower than intended.
At 8 minutes past Pit Station calls Telemetry: "Message from Dog." ('Dead Dog' is Andy Green's RAF callsign). "Possible problem with computer. He is unable to diagnose and will leave it running."
As you move the Merlo to your position for the next run, you realise that this is the best photographic chance you have had yet. Instead of the sun being high on the other side of the car, it is low, and directly behind you as you aim your lenses up the tracks. Photographers call this the 'golden hour', and with good reason - the light is superb.
Across the desert two long freight trains head towards each other and pass in the loop. Mobile Recs advises Pit Station that a second run will take place within the hour turnround target. SSC comes back on air, requesting temperature and pressure - Jayne responds with 23.6C and 884mb. At 1746 we hear: "SSC, that's copied. All stations stand by. SSC estimates engine start in 5 minutes."
At 1750 Robbie Kraike reports that the Palouste is functioning at idle - the sick air-starter is working very well today after Robert Atkinson has given it some attention. A minute later SSC is armed and the engines are starting.
Jayne checks that all operational team members are ready. At 1754 she announces a temporary hold - unable to hear SSC and Team 2 we have no idea why. Shortly after the run is cancelled - SSC has a technical problem. It will be a long, long tow home, and you won't be getting those pictures today.
On return to the Desert Pits we hear that Comp 2 had fallen over on the run - and that the processor boards had been exchanged before the run. A faulty processor is now suspected - if you have a Texas Instruments TMS320C25 Digital Signal Processor IC in a PGA package that you can let us have, please see our Help Wanted section. The second run was cancelled after a problem developed in the hydraulic system at the last minute - that will be fixed tomorrow.
You hear that the media coverage of today's runs has been excellent- Sky News have broadcast 1½ hours of live footage to 40 million people, and everyone in the Press Area is very evidently excited by what is going on. Indeed, we understand that Sky's telephones were inundated after this morning's broadcast - by people asking when they would do it again!
We are making progress with working out the bugs - and we'll be sure to let you know when Sky do their next live broadcast!
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