Controller clears air carrier to an occupied altitude and changes his mind too late to avoid a TCASI...

Attributes
ACN	450340
Time
Date	199909
Day	Mon
Local Time Of Day	1201 To 1800
Place
State Reference	PA
Altitude	msl bound lower : 24000 msl bound upper : 26000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny.artcc tower : pvd.tower
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	cruise : descent cruise : enroute altitude change
Route In Use	enroute airway : j220.airway
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zny.artcc
Operator	Other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 230 flight time total : 18000 flight time type : 8000
ASRS Report	450340
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe
Independent Detector	aircraft equipment : tcas other controllera other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Cruising at FL260. ATC cleared us to descend to FL240 and requested a good rate of descent. He cleared us to proceed direct buf passing FL250. We were J220 heading north 50-75 mi south of sfk. Passing FL245 on the descent, ATC requested we maintain FL250. I stated we were at FL242 and would climb to FL250. Passing FL250 we turned direct buf. At that time we noted traffic at 3 O'clock at FL240. We got a TA as the traffic continued to move closer. As we started our climb back to FL250, we got an RA to climb at about 2000 FPM. We complied. Between FL245-FL250 we got a 'clear of traffic.' ATC asked us our altitude. We stated FL242. He asked to report level FL250. We reported level and reported the RA. The sequence of events above is not exact, as many things happened at the same time.

Original NASA ASRS Text

Title: CTLR CLRS ACR TO AN OCCUPIED ALT AND CHANGES HIS MIND TOO LATE TO AVOID A TCASII RA.

Narrative: CRUISING AT FL260. ATC CLRED US TO DSND TO FL240 AND REQUESTED A GOOD RATE OF DSCNT. HE CLRED US TO PROCEED DIRECT BUF PASSING FL250. WE WERE J220 HDG N 50-75 MI S OF SFK. PASSING FL245 ON THE DSCNT, ATC REQUESTED WE MAINTAIN FL250. I STATED WE WERE AT FL242 AND WOULD CLB TO FL250. PASSING FL250 WE TURNED DIRECT BUF. AT THAT TIME WE NOTED TFC AT 3 O'CLOCK AT FL240. WE GOT A TA AS THE TFC CONTINUED TO MOVE CLOSER. AS WE STARTED OUR CLB BACK TO FL250, WE GOT AN RA TO CLB AT ABOUT 2000 FPM. WE COMPLIED. BTWN FL245-FL250 WE GOT A 'CLR OF TFC.' ATC ASKED US OUR ALT. WE STATED FL242. HE ASKED TO RPT LEVEL FL250. WE RPTED LEVEL AND RPTED THE RA. THE SEQUENCE OF EVENTS ABOVE IS NOT EXACT, AS MANY THINGS HAPPENED AT THE SAME TIME.

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.

Controller clears air carrier to an occupied altitude and changes his mind too late to avoid a TCASII RA.