A ZME controller and an F-18 crew describe an altitude deviation during descent from FL350 to 340 ca...

Attributes
ACN	986150
Time
Date	201112
Local Time Of Day	1201-1800
Place
Locale Reference	ZME.ARTCC
State Reference	TN
Aircraft 1
Make Model Name	Hornet (F-18)
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	IFR
Aircraft 2
Make Model Name	DC-10 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Enroute
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 23
Person 2
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Commercial
Experience	Flight Crew Last 90 Days 38 Flight Crew Total 900 Flight Crew Type 630
Events
Anomaly	Conflict Airborne Conflict Deviation - Altitude Overshoot Deviation - Procedural Clearance

Narrative:

One aircraft I was working was an F-18. I noticed he was landing nmm; and that he was an F-18; rvsm; and level FL350. At the time; the F-18 was located approximately 50 NM west of jan. I had to descend him due to the proximity of his destination and the fact that he had traffic at the same altitude. I called R45 and requested FL330; which the controller unabled. However; the controller then approved FL340. I quick-looked sector 45; and noticed that he had traffic east of the F-18; a DC10 (I think this was the type aircraft). I advised R45 that I was going to descend the F-18 to FL340 and turn him twenty degrees right so that that controller could descend him reference his traffic. I instructed the F-18 to descend to FL340 and turn twenty degrees right for traffic. I confirmed the read back; then switched him to R45's frequency. Thirty seconds or so later; I heard R45 ask the F-18 what his altitude was. I then learned that the F-18 had descended below his assigned altitude and that the DC10 had responded to a TCAS alert. I have no particular recommendations as pilot/controller read back/hear back has been emphasized many times in the past. I confirmed my clearance to the F-18 by hear back; thereby completing my part of the communication with the pilot reference my clearance.

Original NASA ASRS Text

Title: A ZME Controller and an F-18 crew describe an altitude deviation during descent from FL350 to 340 causing a TCAS alert in a DC10 at FL330.

Narrative: One aircraft I was working was an F-18. I noticed he was landing NMM; and that he was an F-18; RVSM; and level FL350. At the time; the F-18 was located approximately 50 NM west of JAN. I had to descend him due to the proximity of his destination and the fact that he had traffic at the same altitude. I called R45 and requested FL330; which the Controller unabled. However; the Controller then approved FL340. I quick-looked Sector 45; and noticed that he had traffic east of the F-18; a DC10 (I think this was the type aircraft). I advised R45 that I was going to descend the F-18 to FL340 and turn him twenty degrees right so that that Controller could descend him reference his traffic. I instructed the F-18 to descend to FL340 and turn twenty degrees right for traffic. I confirmed the read back; then switched him to R45's frequency. Thirty seconds or so later; I heard R45 ask the F-18 what his altitude was. I then learned that the F-18 had descended below his assigned altitude and that The DC10 had responded to a TCAS alert. I have no particular recommendations as pilot/controller read back/hear back has been emphasized many times in the past. I confirmed my clearance to the F-18 by hear back; thereby completing my part of the communication with the pilot reference my clearance.

Data retrieved from NASA's ASRS site as of April 2012 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 ZME controller and an F-18 crew describe an altitude deviation during descent from FL350 to 340 causing a TCAS alert in a DC10 at FL330.