Narrative:

We were cleared for takeoff on runway 30 at iad. The captain and I scanned the arrival area for our runway; taxied onto the runway and began the takeoff roll. As we accelerated through 60 KTS; the captain said 'look at this.' I looked up to see an rj passing over us (approximately 150 ft) on landing approach to runway 1L. We continued a normal takeoff and flight to ZZZ. I don't know if this is acceptable separation at iad; but it looked too close to me. We checked the approach path for our runway; but; knowing that they were landing on runway 1L and 1R; we should have been more observant of the approach path to runway 1L.

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Original NASA ASRS Text

Title: B757 EXPRESSED CONCERN REGARDING ATC SEPARATION PROVIDED BTWN TKOFS ON RWY 30 AND LNDGS ON RWY 1L.

Narrative: WE WERE CLRED FOR TKOF ON RWY 30 AT IAD. THE CAPT AND I SCANNED THE ARR AREA FOR OUR RWY; TAXIED ONTO THE RWY AND BEGAN THE TKOF ROLL. AS WE ACCELERATED THROUGH 60 KTS; THE CAPT SAID 'LOOK AT THIS.' I LOOKED UP TO SEE AN RJ PASSING OVER US (APPROX 150 FT) ON LNDG APCH TO RWY 1L. WE CONTINUED A NORMAL TKOF AND FLT TO ZZZ. I DON'T KNOW IF THIS IS ACCEPTABLE SEPARATION AT IAD; BUT IT LOOKED TOO CLOSE TO ME. WE CHKED THE APCH PATH FOR OUR RWY; BUT; KNOWING THAT THEY WERE LNDG ON RWY 1L AND 1R; WE SHOULD HAVE BEEN MORE OBSERVANT OF THE APCH PATH TO RWY 1L.

Data retrieved from NASA's ASRS site as of January 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.