Learjet 60 flight crew interpret speed restr for heading change.

Attributes
ACN	537035
Time
Date	200201
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lga.airport
State Reference	NY
Altitude	msl single value : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : n90.tracon
Operator	general aviation : corporate
Make Model Name	Learjet 60
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	approach : charted visual
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : n90.tracon
Operator	Other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : charted visual
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 120 flight time total : 5500 flight time type : 2000
ASRS Report	537035
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Events
Anomaly	non adherence : clearance non adherence : published procedure other spatial deviation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : returned to intended or assigned course
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	ATC Human Performance

Narrative:

We were on the approach for lga by going visual up the hudson river. The controller told us to fly 180 degree heading which would give us a right turn of about 60-70 degrees to the right. We started our turn to the right to a 180 degree heading, which I replied 'right turn heading 180 degrees.' halfway through the turn, we noticed that we would be cutting in front of traffic that was already lined up in 10 mi in trail. We questioned the controller if the 180 degrees was a heading or a speed of 180 KTS. The controller replied it was 180 KTS. We immediately turned back to our original flight path up the hudson river. No conflicts or query by the controller took place. Some misunderstanding between us and the controller resulted in a turn towards traffic, but upon readback of the instructions, the controller never corrected us!

Original NASA ASRS Text

Title: LEARJET 60 FLC INTERPRET SPD RESTR FOR HEADING CHANGE.

Narrative: WE WERE ON THE APCH FOR LGA BY GOING VISUAL UP THE HUDSON RIVER. THE CTLR TOLD US TO FLY 180 DEG HDG WHICH WOULD GIVE US A R TURN OF ABOUT 60-70 DEGS TO THE R. WE STARTED OUR TURN TO THE R TO A 180 DEG HDG, WHICH I REPLIED 'R TURN HEADING 180 DEGS.' HALFWAY THROUGH THE TURN, WE NOTICED THAT WE WOULD BE CUTTING IN FRONT OF TFC THAT WAS ALREADY LINED UP IN 10 MI IN TRAIL. WE QUESTIONED THE CTLR IF THE 180 DEGS WAS A HEADING OR A SPD OF 180 KTS. THE CTLR REPLIED IT WAS 180 KTS. WE IMMEDIATELY TURNED BACK TO OUR ORIGINAL FLT PATH UP THE HUDSON RIVER. NO CONFLICTS OR QUERY BY THE CTLR TOOK PLACE. SOME MISUNDERSTANDING BTWN US AND THE CTLR RESULTED IN A TURN TOWARDS TFC, BUT UPON READBACK OF THE INSTRUCTIONS, THE CTLR NEVER CORRECTED US!

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.