Black Knight - BK09

BK09, the second two-stage vehicle, was most successful. Separation of the second stage, initiation of the second stage boost (by Phillips ionisation gauge) and separation of the head from the second stage boost was satisfactory. The second stage boost "lit up" at the correct height on the downward trajectory prior to re-entry and a re-entry velocity of 15,000 ft/sec was achieved at 200,000 f t. The tape recorder in the head recorded data during re-entry down to 80,000 ft.

Just prior to this an abnormal and completely unexpected increase in head oscillation occurred. The head broke up shortly after this and unfortunately the last inch or so of tape which had passed through the tape head was lost. This corresponded to the period immediately prior to head break-up. The break-up of the head at a low height during re-entry indicated that either the plank construction of the head was unsatisfactory or abnormally high loading was applied during re-entry, may be resulting from an unstable oscillation. A single upper-atmosphere experiment, measurement of Sporadic E, worked satisfactorily. The "Gaslight" ground instrumentation (Photometers, Radiometers and Spectral ballistic cameras) obtained some re-entry information. The head conical surface durestos planks were recovered and peak temperature during re-entry estimated

Number Stages Date local
time Empty
wt [lbs] HTP
[lbs] Kerosene
[lbs} All up
wt [lbs] Burn-out
time [s] Apogee
miles

09 2 21 6 60 19.35 2 022 10 375 1 342 13 739 149.5 301