Narrative:

With first officer as PF flying the MD90 noise abatement profile at sna, aircraft at steep deck angle (approximately 15 degrees), power cut back to 1.25 EPR, airspeed at V2 + 10 per the profile. While approximately 4 isna DME climbing through 2100 ft MSL outbound for 3000 ft MSL, TCAS RA alerted us to pop-up traffic at close range. Aural advisory 'traffic, traffic.' immediately went to resolution alert, 'climb, monitor vertical speed, climb.' vsi RA was commanding a rate of 3300 FPM with our current climb rate at 2200 FPM with power way back at 1.25 EPR. Conflict red box was superimposed under our aircraft symbol on the vsi display. We disconnected the automatic-throttles immediately, advanced power and increased our climb rate. However, with the power back so far we did not reach target climb rate until we were clear of conflict. Crew never did see the conflict aircraft and vsi display indicated -02 with the right wing of our aircraft symbol superimposed over the red box of the conflict aircraft. We notified tower of our RA response and were informed that conflict was probably a cessna. Controller seemed unaware of the aircraft until we advised him. Tower had advised us of VFR traffic at 3500 MSL during our take-off clearance, so we were effectively sandwiched between two VFR aircraft while trying to fly this noise-abatement profile. In my opinion, this sna noise abatement procedure is hazardous. It requires steep deck angles, obscuring visual lookout. Complicated procedures require an abnormal amount of heads-down composite flying, detracting from visual lookout. Also with steep deck angle, aircraft is at V2 + 10 knots without much ability to trade some airspeed for altitude. Additionally, the reduced power setting significantly increases the spool up time, thereby limiting our maneuvering potential for pop-up RA's such as this which require steep climbs. I strongly recommend that this sna noise abatement procedure be drastically simplified or eliminated before we dump an aircraft on top of newport beach. This procedure is dangerous. Callback conversation with reporter revealed the following: reporter said that it was a sunday and the traffic below that was unreported was in the class C without contact with sna tower. The traffic above was previously reported with the takeoff clearance and a restricting altitude had been issued to avoid it. The reporter said that they were never able to restore power in time to increase to the climb rate commanded by TCAS. He attributes this to the very close spacing. He repeated his claim that something must be done to change the procedures so that there is some maneuvering space left to the pilot. He also sees a hazard created by the procedure in the event of an engine failure directly after takeoff.

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Original NASA ASRS Text

Title: MD90 FLYING NOISE ABATEMENT PROFILE FROM SNA HAS TCAS RA DURING REDUCED PWR PORTION. PLT WAS UNABLE TO RESTORE PWR TO COMPLETE COMMANDED AVOIDANCE MANEUVER BEFORE PASSING TFC LESS THAN 200 FT BELOW.

Narrative: WITH FO AS PF FLYING THE MD90 NOISE ABATEMENT PROFILE AT SNA, AIRCRAFT AT STEEP DECK ANGLE (APPROX 15 DEGS), POWER CUT BACK TO 1.25 EPR, AIRSPEED AT V2 + 10 PER THE PROFILE. WHILE APPROX 4 ISNA DME CLIMBING THROUGH 2100 FT MSL OUTBOUND FOR 3000 FT MSL, TCAS RA ALERTED US TO POP-UP TRAFFIC AT CLOSE RANGE. AURAL ADVISORY 'TRAFFIC, TRAFFIC.' IMMEDIATELY WENT TO RESOLUTION ALERT, 'CLB, MONITOR VERT SPD, CLB.' VSI RA WAS COMMANDING A RATE OF 3300 FPM WITH OUR CURRENT CLB RATE AT 2200 FPM WITH POWER WAY BACK AT 1.25 EPR. CONFLICT RED BOX WAS SUPERIMPOSED UNDER OUR ACFT SYMBOL ON THE VSI DISPLAY. WE DISCONNECTED THE AUTO-THROTTLES IMMEDIATELY, ADVANCED POWER AND INCREASED OUR CLB RATE. HOWEVER, WITH THE POWER BACK SO FAR WE DID NOT REACH TARGET CLB RATE UNTIL WE WERE CLEAR OF CONFLICT. CREW NEVER DID SEE THE CONFLICT AIRCRAFT AND VSI DISPLAY INDICATED -02 WITH THE RIGHT WING OF OUR ACFT SYMBOL SUPERIMPOSED OVER THE RED BOX OF THE CONFLICT ACFT. WE NOTIFIED TOWER OF OUR RA RESPONSE AND WERE INFORMED THAT CONFLICT WAS PROBABLY A CESSNA. CONTROLLER SEEMED UNAWARE OF THE ACFT UNTIL WE ADVISED HIM. TWR HAD ADVISED US OF VFR TFC AT 3500 MSL DURING OUR TAKE-OFF CLRNC, SO WE WERE EFFECTIVELY SANDWICHED BETWEEN TWO VFR ACFT WHILE TRYING TO FLY THIS NOISE-ABATEMENT PROFILE. IN MY OPINION, THIS SNA NOISE ABATEMENT PROC IS HAZARDOUS. IT REQUIRES STEEP DECK ANGLES, OBSCURING VISUAL LOOKOUT. COMPLICATED PROCS REQUIRE AN ABNORMAL AMOUNT OF HEADS-DOWN COMPOSITE FLYING, DETRACTING FROM VISUAL LOOKOUT. ALSO WITH STEEP DECK ANGLE, ACFT IS AT V2 + 10 KNOTS WITHOUT MUCH ABILITY TO TRADE SOME AIRSPEED FOR ALT. ADDITIONALLY, THE REDUCED PWR SETTING SIGNIFICANTLY INCREASES THE SPOOL UP TIME, THEREBY LIMITING OUR MANEUVERING POTENTIAL FOR POP-UP RA'S SUCH AS THIS WHICH REQUIRE STEEP CLBS. I STRONGLY RECOMMEND THAT THIS SNA NOISE ABATEMENT PROC BE DRASTICALLY SIMPLIFIED OR ELIMINATED BEFORE WE DUMP AN ACFT ON TOP OF NEWPORT BEACH. THIS PROC IS DANGEROUS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR SAID THAT IT WAS A SUNDAY AND THE TRAFFIC BELOW THAT WAS UNREPORTED WAS IN THE CLASS C WITHOUT CONTACT WITH SNA TWR. THE TRAFFIC ABOVE WAS PREVIOUSLY REPORTED WITH THE TAKEOFF CLRNC AND A RESTRICTING ALT HAD BEEN ISSUED TO AVOID IT. THE RPTR SAID THAT THEY WERE NEVER ABLE TO RESTORE POWER IN TIME TO INCREASE TO THE CLIMB RATE COMMANDED BY TCAS. HE ATTRIBUTES THIS TO THE VERY CLOSE SPACING. HE REPEATED HIS CLAIM THAT SOMETHING MUST BE DONE TO CHANGE THE PROCS SO THAT THERE IS SOME MANEUVERING SPACE LEFT TO THE PILOT. HE ALSO SEES A HAZARD CREATED BY THE PROC IN THE EVENT OF AN ENGINE FAILURE DIRECTLY AFTER TAKEOFF.

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.