Run report – Run 8 – 6 Oct 17
Aim
Complete the braking bedding in process for the front right brake, using higher speed (Profile 4, 100 mph).
Operation
Weather 13C, 1015 mb. Lovely day, broken clouds.
- 1330 hrs. Wind 12 o/c, 7 kt. D2 to D4
- Fuel 48 to 38, engine run time 5:00
- Profile 4, aiming for 100 mph, using max dry
- Max dry up to 90 mph, then idle selected. Speed overswing to 120 mph as engine wound down
- 50-55 bar brake pressure, giving all 4 brake temps peak at 350-370C (the hottest, by just 2C, was the front right!) and just under 0.4G
- Total distance for accel/decel approx. 2100ft
- Uneveness in Delta taxiway worked the suspension noticeably for the first time. The ride and handling felt well-controlled throughout
Summary
Front right brake has now very much joined the party and is ready for higher speeds. Handling and performance are both excellent.
Procedural points
- EJ200 takes a couple of seconds to stop producing thrust. Selection of idle needs to be anticipated by a bigger margin (~30 mph?), which will be explored in the next couple of runs
- Brake performance at 0.4G validates the assumed worst-case planning figures of 0.2G for a brake failure during a run
- Profile 4 calculated distance is very close to the achieved 2100ft, the first chance we’ve had to correlate predicted and actual distances
Technical points
- Comms, distance indicator as previous runs
Run report – Run 9 – 10 Oct 17
Aim
Now that the brakes are bedded in, continue to expand the performance envelope and understand the power-off overswing of the EJ200. Target 100 mph at max dry.
Operation
Delta taxiway, approx. 4000 ft available, with overruns if required.
Weather 17C, 1003 mb, strong crosswind. Overcast with recent drizzle. Damp surface gradually drying (moistness 3/5)
- 1200 hrs. Wind 3 o/c 15 kt. D4 to D2
- Fuel 60 to 49%, engine run time 6:30
- Profile 4, max dry to 70, select idle, peak speed 103 mph. Limited power vs brakes to complete the run
- Cautious increase in brake pressure up to 50 bar, good braking action on damp/wet surface. Front right brake temp low (FL 300C, FR 150C, rears 250C)
Summary
Speed overswing after selecting idle appears to be around 30 mph from max dry.
Procedural points
- Wet braking action is good, no significant limitation on ops.
Technical points
- Car comms with Tower are still poor at D2. Relay from Recovery/Eng working well.
