C550. Controller cleared aircraft to descend through occupied altitude in ZID class a.

Attributes
ACN	513642
Time
Date	200106
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : zid.artcc
State Reference	IN
Altitude	msl bound lower : 20900 msl bound upper : 22000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid.artcc
Operator	general aviation : corporate
Make Model Name	Citation II S2/Bravo
Operating Under FAR Part	Part 91
Flight Phase	descent : vacating altitude
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain
Qualification	pilot : cfi pilot : atp pilot : multi engine
Experience	flight time last 90 days : 60 flight time total : 7000 flight time type : 400
ASRS Report	513642
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : far other anomaly other
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	controller : issued new clearance controller : issued alert none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error
Situations
ATC Facility	procedure or policy : zid.artcc

Narrative:

While descending from altitude to FL220 we were given a clearance to descend to FL200 with traffic 10 mi north at FL210. First officer responded with descend and maintain FL200. At that time we were descending 2200 FPM through 22500 ft. As we past approximately 20900 ft the controller asked us what altitude we were descending to and the first officer responded FL200. The controller cut him off and said we were told to maintain FL220. There were further interrupted exchanges with ATC and we corrected back to FL220. The controller was very upset with us and stated that he thought that we possibly made an altitude deviation and that we needed to call center upon arrival. He also made a comment to the other aircraft involved, something like 'I don't know what they were doing at that altitude.' the controller seemed disinterested when the first officer tried to explain that he cleared us to FL200. Upon landing, I called our director of operations. He called ZID. He spoke to a manager and was told upon review of the tapes that the controller did indeed clear us to FL200. He further stated that there would be no action against the crew and that we were out of it. We don't know if the other aircraft had to make a heading correction for avoidance. Our TCASII did not alert us of danger. It seems that the situation became worse when the controller demanded us to go back to FL220. We were coming down at a good rate and would have leveled at FL200 in a matter of seconds. It was a busy time and things happened very quickly. Communication broke down. ATC talking, not listening.

Original NASA ASRS Text

Title: C550. CTLR CLRED ACFT TO DSND THROUGH OCCUPIED ALT IN ZID CLASS A.

Narrative: WHILE DSNDING FROM ALT TO FL220 WE WERE GIVEN A CLRNC TO DSND TO FL200 WITH TFC 10 MI N AT FL210. FO RESPONDED WITH DSND AND MAINTAIN FL200. AT THAT TIME WE WERE DSNDING 2200 FPM THROUGH 22500 FT. AS WE PAST APPROX 20900 FT THE CTLR ASKED US WHAT ALT WE WERE DSNDING TO AND THE FO RESPONDED FL200. THE CTLR CUT HIM OFF AND SAID WE WERE TOLD TO MAINTAIN FL220. THERE WERE FURTHER INTERRUPTED EXCHANGES WITH ATC AND WE CORRECTED BACK TO FL220. THE CTLR WAS VERY UPSET WITH US AND STATED THAT HE THOUGHT THAT WE POSSIBLY MADE AN ALTDEV AND THAT WE NEEDED TO CALL CTR UPON ARR. HE ALSO MADE A COMMENT TO THE OTHER ACFT INVOLVED, SOMETHING LIKE 'I DON'T KNOW WHAT THEY WERE DOING AT THAT ALT.' THE CTLR SEEMED DISINTERESTED WHEN THE FO TRIED TO EXPLAIN THAT HE CLRED US TO FL200. UPON LNDG, I CALLED OUR DIRECTOR OF OPS. HE CALLED ZID. HE SPOKE TO A MGR AND WAS TOLD UPON REVIEW OF THE TAPES THAT THE CTLR DID INDEED CLR US TO FL200. HE FURTHER STATED THAT THERE WOULD BE NO ACTION AGAINST THE CREW AND THAT WE WERE OUT OF IT. WE DON'T KNOW IF THE OTHER ACFT HAD TO MAKE A HEADING CORRECTION FOR AVOIDANCE. OUR TCASII DID NOT ALERT US OF DANGER. IT SEEMS THAT THE SIT BECAME WORSE WHEN THE CTLR DEMANDED US TO GO BACK TO FL220. WE WERE COMING DOWN AT A GOOD RATE AND WOULD HAVE LEVELED AT FL200 IN A MATTER OF SECONDS. IT WAS A BUSY TIME AND THINGS HAPPENED VERY QUICKLY. COM BROKE DOWN. ATC TALKING, NOT LISTENING.

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.