Altitude deviation. Undershoot in descent.

Attributes
ACN	144778
Time
Date	199005
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : tth
State Reference	IN
Altitude	msl bound lower : 24000 msl bound upper : 28000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid
Operator	general aviation : corporate
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp pilot : cfi
Experience	flight time last 90 days : 100 flight time total : 7000 flight time type : 3500
ASRS Report	144778
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : undershoot non adherence : clearance
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were cruising southbound to the tth VOR at 28000'. The radio had been silent for 10-15 mins. Upon crossing the VOR the controller told us we had been cleared to cross the VOR at 24000'. I looked at the PNF he looked at me. Neither of us remembered being given that clearance. We looked at the alerter and it was set to 24000'. Neither of us remember setting it. We do not have a cvr installed yet, so no way to verify the events, and it was not the time to question the controller. We reported out of 28000' and descended to 24000'. We were 1 hour behind schedule due to WX delays. Thunderstorms had been reported at destination. I was working radar and the PNF was on #2 talking to FSS prior to reaching the tth VOR. Had we both been so caught up in secondary duties that we both forgot about a clearance that was apparently issued 15 mins earlier?

Original NASA ASRS Text

Title: ALT DEVIATION. UNDERSHOOT IN DESCENT.

Narrative: WE WERE CRUISING SBND TO THE TTH VOR AT 28000'. THE RADIO HAD BEEN SILENT FOR 10-15 MINS. UPON XING THE VOR THE CTLR TOLD US WE HAD BEEN CLRED TO CROSS THE VOR AT 24000'. I LOOKED AT THE PNF HE LOOKED AT ME. NEITHER OF US REMEMBERED BEING GIVEN THAT CLRNC. WE LOOKED AT THE ALERTER AND IT WAS SET TO 24000'. NEITHER OF US REMEMBER SETTING IT. WE DO NOT HAVE A CVR INSTALLED YET, SO NO WAY TO VERIFY THE EVENTS, AND IT WAS NOT THE TIME TO QUESTION THE CTLR. WE RPTED OUT OF 28000' AND DSNDED TO 24000'. WE WERE 1 HR BEHIND SCHEDULE DUE TO WX DELAYS. TSTMS HAD BEEN RPTED AT DEST. I WAS WORKING RADAR AND THE PNF WAS ON #2 TALKING TO FSS PRIOR TO REACHING THE TTH VOR. HAD WE BOTH BEEN SO CAUGHT UP IN SECONDARY DUTIES THAT WE BOTH FORGOT ABOUT A CLRNC THAT WAS APPARENTLY ISSUED 15 MINS EARLIER?

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.