Computer track of aircraft on radar scope inadvertently cancelled.

Attributes
ACN	121173
Time
Date	198908
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : zdc
State Reference	DC
Altitude	msl bound lower : 24000 msl bound upper : 24000
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	other
Make Model Name	Military Transport
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 9
ASRS Report	121173
Person 2
Affiliation	government : military
Function	flight crew : captain oversight : pic
Qualification	pilot : military
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

I was working the radar position at sector 20. When I attempted to enter an interim altitude of FL240 on aircraft mlt X, the response of the computer to my entry was that it cancelled the track on the aircraft. A 'dart' was run and it showed that I entered a 'drop track' message. However, I do not believe that to be true. I remember entering FL240 and the cid #, and I'm pretty certain that I hit the 'interim altitude' button. There is a considerable distance between that button and the 'cancel track' button. I believe that the error was made by the equipment. I also know of similar incidents in the past involving a 'drop track,' resulting from an attempted 'interim altitude' message. If this were to occur during busy traffic, the controller could forget about the aircraft.

Original NASA ASRS Text

Title: COMPUTER TRACK OF ACFT ON RADAR SCOPE INADVERTENTLY CANCELLED.

Narrative: I WAS WORKING THE RADAR POS AT SECTOR 20. WHEN I ATTEMPTED TO ENTER AN INTERIM ALT OF FL240 ON ACFT MLT X, THE RESPONSE OF THE COMPUTER TO MY ENTRY WAS THAT IT CANCELLED THE TRACK ON THE ACFT. A 'DART' WAS RUN AND IT SHOWED THAT I ENTERED A 'DROP TRACK' MESSAGE. HOWEVER, I DO NOT BELIEVE THAT TO BE TRUE. I REMEMBER ENTERING FL240 AND THE CID #, AND I'M PRETTY CERTAIN THAT I HIT THE 'INTERIM ALT' BUTTON. THERE IS A CONSIDERABLE DISTANCE BTWN THAT BUTTON AND THE 'CANCEL TRACK' BUTTON. I BELIEVE THAT THE ERROR WAS MADE BY THE EQUIP. I ALSO KNOW OF SIMILAR INCIDENTS IN THE PAST INVOLVING A 'DROP TRACK,' RESULTING FROM AN ATTEMPTED 'INTERIM ALT' MESSAGE. IF THIS WERE TO OCCUR DURING BUSY TFC, THE CTLR COULD FORGET ABOUT THE ACFT.

Data retrieved from NASA's ASRS site as of August 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.