Narrative:

The H25B was instructed to exit runway 16R and contact ground. The local 1 controller crossed the PA34 and cleared the PA34 for takeoff runway 16L. The PA34 did not cross and took off on runway 16R. While the PA34 was taking off; the H25B was not clear of the runway yet. The PA34 was now airborne and yet the H25B was still not off the runway and local control #1 controller instructed the H25B to exit the high speed taxiway. He did just that; but the PA34 was already airborne. A C172 later asked if he should have said something when he noticed the PA34 taking off the wrong runway.

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Original NASA ASRS Text

Title: VNY CTLR DESCRIBED PLT DEV WHEN ACFT CLEARED FOR DEP ON RWY 16L DEPARTED RWY 16R; FLYING OVER LNDG ACFT ON RWY 16R EXITING RWY.

Narrative: THE H25B WAS INSTRUCTED TO EXIT RWY 16R AND CONTACT GND. THE LCL 1 CTLR CROSSED THE PA34 AND CLRED THE PA34 FOR TKOF RWY 16L. THE PA34 DID NOT CROSS AND TOOK OFF ON RWY 16R. WHILE THE PA34 WAS TAKING OFF; THE H25B WAS NOT CLR OF THE RWY YET. THE PA34 WAS NOW AIRBORNE AND YET THE H25B WAS STILL NOT OFF THE RWY AND LCL CTL #1 CTLR INSTRUCTED THE H25B TO EXIT THE HIGH SPD TXWY. HE DID JUST THAT; BUT THE PA34 WAS ALREADY AIRBORNE. A C172 LATER ASKED IF HE SHOULD HAVE SAID SOMETHING WHEN HE NOTICED THE PA34 TAKING OFF THE WRONG RWY.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.