Narrative:

Air carrier #1 heavy DC8 on departure slow climb and close to MVA. I instructed him to increase rate of turn for MVA. Replied roger. Next departure was B757, 3.8 mi behind heavy. 5 mi is required, non waiverable and visible separation cannot be applied. Aircraft on downwind at 9000 ft. Departure climbing to 8000 ft. DC8 was about 5 flying mi from runway end still only out of about 6800 ft. B757 was 3.8 mi behind already climbing out of 6500 ft. Unable to climb either aircraft due to downwind traffic, could not turn because of close proximity to terrain and final was descending abeam airport.

Google
 

Original NASA ASRS Text

Title: LCL CTLR DEPARTED A B757 BEHIND A SLOW CLBING HVY DC8 WITHOUT THE REQUIRED SEPARATION.

Narrative: ACR #1 HVY DC8 ON DEP SLOW CLB AND CLOSE TO MVA. I INSTRUCTED HIM TO INCREASE RATE OF TURN FOR MVA. REPLIED ROGER. NEXT DEP WAS B757, 3.8 MI BEHIND HVY. 5 MI IS REQUIRED, NON WAIVERABLE AND VISIBLE SEPARATION CANNOT BE APPLIED. ACFT ON DOWNWIND AT 9000 FT. DEP CLBING TO 8000 FT. DC8 WAS ABOUT 5 FLYING MI FROM RWY END STILL ONLY OUT OF ABOUT 6800 FT. B757 WAS 3.8 MI BEHIND ALREADY CLBING OUT OF 6500 FT. UNABLE TO CLB EITHER ACFT DUE TO DOWNWIND TFC, COULD NOT TURN BECAUSE OF CLOSE PROX TO TERRAIN AND FINAL WAS DSNDING ABEAM ARPT.

Data retrieved from NASA's ASRS site as of July 2007 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.