A CPR L329 FLC HIT THE WAKE OF A PRECEDING B727 JUST AFTER LIFTOFF FROM RWY 36 IN DCA. THE ACFT ROLLED UP TO 30 DEGS R THEN L WITH UP TO 5 DEGS OF YAW IN THE OPPOSITE DIRECTION. THE FLC CONTINUED THEIR DEP BY STAYING TO ONE SIDE OF THE B727'S COURSE UNTIL THEY GOT ABOVE IT.

Narrative

ON DEP FROM DCA; RWY 36. WE ENCOUNTERED MILD WAKE TURB FROM DEPARTING B727. REQUIRED 70% OF YOKE DEFLECTION (ROLL) TO MAINTAIN WINGS LEVEL. OPTED TO MAINTAIN RWY HDG FOR 30 SECONDS AND FLY UPWIND OF VORTICES. NEW NOISE ABATEMENT REQUIRES IMMEDIATE L TURN. UNABLE TO ADVISE LCL CTL DUE TO FREQ CONGESTION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR IS A CAPT AND CHIEF PLT FOR A CPR FLT DEPT AND HE WAS FLYING A LOCKHEED JETSTAR WHEN HE HIT THE WAKE OF A B727 JUST AFTER LIFTOFF. HE SAID THAT HE HAD JUST CALLED 'GEAR UP' WHEN THE ACFT STARTED THE FIRST ROLL TO THE R. HE TOLD THE FO TO LEAVE THE GEAR DOWN FOR THE MOMENT. AFTER THEY WERE OVER THE RIVER AT DCA THEY RETRACTED THE GEAR. HE SAID THAT THE ROLL WAS VERY RAPID AND GOT TO 30 DEGS TO THE R AND THEN TO THE L TO ABOUT 30 DEGS ALSO. HE SAID THAT THE ROLL WAS ACCOMPANIED BY A YAW TO THE OPPOSITE SIDE OF ABOUT 5 DEGS. ALSO THE CLB RATE REDUCED FROM 2000 FPM TO 500 FPM. HE COULD STOP THE ROLL BY PUTTING ABOUT 70 PERCENT OF HIS AILERON'S TRAVEL AGAINST THE DIRECTION OF ROLL. HE DESCRIBED THE MOTION AS BEING LIKE A STRONG DUTCH ROLL. THE RPTR ALLEGED THAT THE CTLR CLRED HIM FOR TKOF AS THE B727 ROTATED; AND THE CAPT ESTIMATES THAT HE WAS ONLY 1 - 1 1/2 MI BEHIND THE B727 WHEN HE ROTATED. HE SAID THAT HE FEELS THAT THE CTLRS AND PLTS OF LARGER CPR ACFT HAVE GOTTEN A BIT CASUAL ABOUT WAKE SEPARATION ON DEP. SOME OF HIS PLTS FELT THAT THEIR CLB PERFORMANCE WAS SO GOOD THAT THEY COULD OUT-CLB THE LARGER ACR'S WAKE. HE SAID THAT HIS BRIEFING TO HIS OWN PLTS HAS CHANGED THEIR UNDERSTANDING AND THEY NOW DO NOT WAIVE THE SEPARATION.