Speed deviation by air carrier on climb out reducing separation.

Attributes
ACN	282721
Time
Date	199409
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sju
State Reference	PR
Altitude	msl bound lower : 5000 msl bound upper : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Shorts SD-360
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct enroute airway : sju
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Shorts SD-360
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 185 flight time total : 2100
ASRS Report	282721
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : flight engineer
Events
Anomaly	non adherence : clearance other anomaly
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were following a company shorts SD3-60 on our climb after departing san juan's luis munoz marin international airport. We had the company in sight and on TCASII and we were given a speed restr of 160 KTS or less. We assumed that this restr was only for climb out, since we were climbing in similar aircraft and therefore had similar speeds. As we leveled off, we set our normal cruise power which yielded about 180 KTS. We advised ATC that we had company in sight twice but there was no response. Again we called ATC advising them that we might overtake company and again, no response. Later, ATC asked us our speed. Since it was higher than what he expected and the separation decreased, he gave us a lower altitude. After our descent, he asked us to call the san juan cerap. On this call we found out that the san juan cerap was experiencing problems with their communications linkage, and the controller was handling several frequencys at a time. This overloaded condition may have prevented the controller of being clear enough therefore leading us to misunderstand his instructions.

Original NASA ASRS Text

Title: SPD DEV BY ACR ON CLBOUT REDUCING SEPARATION.

Narrative: WE WERE FOLLOWING A COMPANY SHORTS SD3-60 ON OUR CLB AFTER DEPARTING SAN JUAN'S LUIS MUNOZ MARIN INTL ARPT. WE HAD THE COMPANY IN SIGHT AND ON TCASII AND WE WERE GIVEN A SPD RESTR OF 160 KTS OR LESS. WE ASSUMED THAT THIS RESTR WAS ONLY FOR CLBOUT, SINCE WE WERE CLBING IN SIMILAR ACFT AND THEREFORE HAD SIMILAR SPDS. AS WE LEVELED OFF, WE SET OUR NORMAL CRUISE PWR WHICH YIELDED ABOUT 180 KTS. WE ADVISED ATC THAT WE HAD COMPANY IN SIGHT TWICE BUT THERE WAS NO RESPONSE. AGAIN WE CALLED ATC ADVISING THEM THAT WE MIGHT OVERTAKE COMPANY AND AGAIN, NO RESPONSE. LATER, ATC ASKED US OUR SPD. SINCE IT WAS HIGHER THAN WHAT HE EXPECTED AND THE SEPARATION DECREASED, HE GAVE US A LOWER ALT. AFTER OUR DSCNT, HE ASKED US TO CALL THE SAN JUAN CERAP. ON THIS CALL WE FOUND OUT THAT THE SAN JUAN CERAP WAS EXPERIENCING PROBS WITH THEIR COMS LINKAGE, AND THE CTLR WAS HANDLING SEVERAL FREQS AT A TIME. THIS OVERLOADED CONDITION MAY HAVE PREVENTED THE CTLR OF BEING CLR ENOUGH THEREFORE LEADING US TO MISUNDERSTAND HIS INSTRUCTIONS.

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.