Commuter flight crew misunderstands altitude assignment departing phl.

Attributes
ACN	461597
Time
Date	200001
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : phl.airport
State Reference	PA
Altitude	msl bound lower : 4000 msl bound upper : 5000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tracon : phl.tracon tracon : elm.tracon
Operator	common carrier : air carrier
Make Model Name	Beech 1900
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial
Route In Use	departure sid : phl b enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 80 flight time total : 4350 flight time type : 1500
ASRS Report	461597
Person 2
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Events
Anomaly	altitude deviation : overshoot non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued advisory flight crew : returned to assigned altitude
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We departed phl on the philadelphia 6 departure which specifies 5000 ft if no lower altitude is assigned. After xferring from departure control to the next en route controller, and then later after leveling at 5000 ft, ATC queried if the previous controller had assigned us 5000 ft because he showed we should be at 4000 ft. We replied that 5000 ft was the assignment. He said that there was no problem, and to descend to 4000 ft 'at pilot's discretion.' the concern is that after switching from tower to departure, and then departure to this controller we reported 'through X altitude for 5000 ft.' so therefore there were 2 occasions where the misunderstanding could have been caught. This is worrisome because of the FAA's possible new policy holding pilots in error when they repeat certain directives back and are not corrected by ATC though the readback was incorrect. This eliminates a check and balance that is vital to the ATC system. I believe in the long run it will promote complacency in controllers and mistakes will not be caught as in the example above. My vote is to retain responsibility on both sides with a renewed sense of cooperation to promote safety.

Original NASA ASRS Text

Title: COMMUTER FLC MISUNDERSTANDS ALT ASSIGNMENT DEPARTING PHL.

Narrative: WE DEPARTED PHL ON THE PHILADELPHIA 6 DEP WHICH SPECIFIES 5000 FT IF NO LOWER ALT IS ASSIGNED. AFTER XFERRING FROM DEP CTL TO THE NEXT ENRTE CTLR, AND THEN LATER AFTER LEVELING AT 5000 FT, ATC QUERIED IF THE PREVIOUS CTLR HAD ASSIGNED US 5000 FT BECAUSE HE SHOWED WE SHOULD BE AT 4000 FT. WE REPLIED THAT 5000 FT WAS THE ASSIGNMENT. HE SAID THAT THERE WAS NO PROB, AND TO DSND TO 4000 FT 'AT PLT'S DISCRETION.' THE CONCERN IS THAT AFTER SWITCHING FROM TWR TO DEP, AND THEN DEP TO THIS CTLR WE RPTED 'THROUGH X ALT FOR 5000 FT.' SO THEREFORE THERE WERE 2 OCCASIONS WHERE THE MISUNDERSTANDING COULD HAVE BEEN CAUGHT. THIS IS WORRISOME BECAUSE OF THE FAA'S POSSIBLE NEW POLICY HOLDING PLTS IN ERROR WHEN THEY REPEAT CERTAIN DIRECTIVES BACK AND ARE NOT CORRECTED BY ATC THOUGH THE READBACK WAS INCORRECT. THIS ELIMINATES A CHK AND BAL THAT IS VITAL TO THE ATC SYS. I BELIEVE IN THE LONG RUN IT WILL PROMOTE COMPLACENCY IN CTLRS AND MISTAKES WILL NOT BE CAUGHT AS IN THE EXAMPLE ABOVE. MY VOTE IS TO RETAIN RESPONSIBILITY ON BOTH SIDES WITH A RENEWED SENSE OF COOPERATION TO PROMOTE SAFETY.

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.