Approach evaluation.

Attributes
ACN	305141
Time
Date	199505
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 1800 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : oak
Operator	common carrier : air carrier
Make Model Name	B747 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach landing other
Route In Use	arrival other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach landing other
Route In Use	approach : visual arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 22000
ASRS Report	305141
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	other anomaly other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other other
Consequence	Other
Supplementary
Air Traffic Incident	other other

Narrative:

ATC asked if we could accept lda DME runway 28R. We said yes and carefully read appropriate bulletin. Captain was flying and ATC vectored us onto the approach. Autoplt intercepted and had difficult time jerking left and right as lda signal was unstable. After capture, approach control turned us north off the lda. Then they vectored us back to lda. Still at 6000 ft, inside aadam. Sensing an imminent missed approach we asked for lower. Finally cleared for approach. ATC slowed us to 150 KTS but our minimum was 153 KTS. ATC told us a B757 would be off our left. Broke out at 1900 ft to 2000 ft and observed a B757 off our left, barely off our wingtip. Maybe we were 200 ft ahead. Where was the promised 3/4 mi stagger promised in the bulletin? We were in the lead position but the lda DME runway 28R does not line up with the runway. I had to maneuver from lucss to runway 28R without getting too close to the B757 off my left. Observations lda DME runway 28R approach: 1) ATC must provide minimum 3/4 mi stagger. 2) sfo ATC needs an approach monitor position to make certain of separation. 3) speed control and sequencing needs to be improved to allow proper separation. 4) if pilots cannot be assured of stagger, this approach plan will fail. Without separation it is unsafe.

Original NASA ASRS Text

Title: APCH EVALUATION.

Narrative: ATC ASKED IF WE COULD ACCEPT LDA DME RWY 28R. WE SAID YES AND CAREFULLY READ APPROPRIATE BULLETIN. CAPT WAS FLYING AND ATC VECTORED US ONTO THE APCH. AUTOPLT INTERCEPTED AND HAD DIFFICULT TIME JERKING L AND R AS LDA SIGNAL WAS UNSTABLE. AFTER CAPTURE, APCH CTL TURNED US N OFF THE LDA. THEN THEY VECTORED US BACK TO LDA. STILL AT 6000 FT, INSIDE AADAM. SENSING AN IMMINENT MISSED APCH WE ASKED FOR LOWER. FINALLY CLRED FOR APCH. ATC SLOWED US TO 150 KTS BUT OUR MINIMUM WAS 153 KTS. ATC TOLD US A B757 WOULD BE OFF OUR L. BROKE OUT AT 1900 FT TO 2000 FT AND OBSERVED A B757 OFF OUR L, BARELY OFF OUR WINGTIP. MAYBE WE WERE 200 FT AHEAD. WHERE WAS THE PROMISED 3/4 MI STAGGER PROMISED IN THE BULLETIN? WE WERE IN THE LEAD POS BUT THE LDA DME RWY 28R DOES NOT LINE UP WITH THE RWY. I HAD TO MANEUVER FROM LUCSS TO RWY 28R WITHOUT GETTING TOO CLOSE TO THE B757 OFF MY L. OBSERVATIONS LDA DME RWY 28R APCH: 1) ATC MUST PROVIDE MINIMUM 3/4 MI STAGGER. 2) SFO ATC NEEDS AN APCH MONITOR POS TO MAKE CERTAIN OF SEPARATION. 3) SPD CTL AND SEQUENCING NEEDS TO BE IMPROVED TO ALLOW PROPER SEPARATION. 4) IF PLTS CANNOT BE ASSURED OF STAGGER, THIS APCH PLAN WILL FAIL. WITHOUT SEPARATION IT IS UNSAFE.

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.