A pilot approaching bwi reports missing an altitude restriction because of confusion about why the r...

Attributes
ACN	751473
Time
Date	200708
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : bwi.airport
State Reference	MD
Altitude	msl single value : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pct.tracon
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	arrival star : ravnn one
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 198
ASRS Report	751473
Events
Anomaly	altitude deviation : crossing restriction not met non adherence : clearance
Independent Detector	other flight crewa
Supplementary
Problem Areas	Chart Or Publication Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Situations
Chart	star : ravnn1

Narrative:

We were cleared the ravnn one arrival into bwi. During the descent I remarked to the first officer (PNF) that the radial out of csn (096) showed we were north of the course depicted on the aircraft display. To me this was unusual because the VOR is usually exactly in agreement with the navigation display. The first officer looked at this for a bit and then remarked that the nottingham six arrival showed the outbound radial from csn to sacco to be the 091 radial. I misinterpreted this comment to mean we were perhaps flying the wrong arrival. We quickly cleared up this miscommunication and determined we were on the proper arrival. During this interval we got high on arrival and crossed the fix udude several hundred feet high. ATC made no comment and there was no conflict with any other aircraft. I feel the outbound radial from csn to sacco needs to be corrected. On the ravnn one arrival it is shown as the 096 radial and the nottingham six arrival shows it as the 091 radial. These are two different radials between the same point; so one is apparently wrong. Incorrect radial on ravnn one arrival between csn and udude.

Original NASA ASRS Text

Title: A PLT APCHING BWI REPORTS MISSING AN ALT RESTRICTION BECAUSE OF CONFUSION ABOUT WHY THE RADIAL OUT OF CSN TO OTT ON THE RAVNN ONE RNAV AND THE NOTTINGHAM SIX ARR ARE DIFFERENT EVEN THOUGH BOTH GO TO SAME FIX.

Narrative: WE WERE CLEARED THE RAVNN ONE ARRIVAL INTO BWI. DURING THE DESCENT I REMARKED TO THE FO (PNF) THAT THE RADIAL OUT OF CSN (096) SHOWED WE WERE NORTH OF THE COURSE DEPICTED ON THE AIRCRAFT DISPLAY. TO ME THIS WAS UNUSUAL BECAUSE THE VOR IS USUALLY EXACTLY IN AGREEMENT WITH THE NAVIGATION DISPLAY. THE FO LOOKED AT THIS FOR A BIT AND THEN REMARKED THAT THE NOTTINGHAM SIX ARRIVAL SHOWED THE OUTBOUND RADIAL FROM CSN TO SACCO TO BE THE 091 RADIAL. I MISINTERPRETED THIS COMMENT TO MEAN WE WERE PERHAPS FLYING THE WRONG ARRIVAL. WE QUICKLY CLEARED UP THIS MISCOMMUNICATION AND DETERMINED WE WERE ON THE PROPER ARRIVAL. DURING THIS INTERVAL WE GOT HIGH ON ARRIVAL AND CROSSED THE FIX UDUDE SEVERAL HUNDRED FEET HIGH. ATC MADE NO COMMENT AND THERE WAS NO CONFLICT WITH ANY OTHER AIRCRAFT. I FEEL THE OUTBOUND RADIAL FROM CSN TO SACCO NEEDS TO BE CORRECTED. ON THE RAVNN ONE ARRIVAL IT IS SHOWN AS THE 096 RADIAL AND THE NOTTINGHAM SIX ARRIVAL SHOWS IT AS THE 091 RADIAL. THESE ARE TWO DIFFERENT RADIALS BETWEEN THE SAME POINT; SO ONE IS APPARENTLY WRONG. INCORRECT RADIAL ON RAVNN ONE ARR BETWEEN CSN AND UDUDE.

Data retrieved from NASA's ASRS site as of January 2009 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.

A pilot approaching bwi reports missing an altitude restriction because of confusion about why the radial out of csn to ott on the ravnn one RNAV and the nottingham six arrival are different even though both go to same fix.