Air carrier medium large transport altitude deviation undershot crossing restriction due speed restr...

Attributes
ACN	86963
Time
Date	198805
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : svm airport : dtw
State Reference	MI
Altitude	msl bound lower : 8000 msl bound upper : 8500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other descent other
Route In Use	enroute airway : zob
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : cfi
Experience	flight time last 90 days : 50 flight time total : 9000 flight time type : 4800
ASRS Report	86963
Person 2
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : undershoot altitude deviation : crossing restriction not met non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

On descent into dtw were given to cross rhyme intersection at 8000'. The center controller then requested the aircraft slow to 250 KTS in the descent. Because of the slower airspeed descent we xed the intersection and were leveling off just at 8000' or slightly above. To avoid crossing intxns with an altitude crossing restriction with such a tight margin, it would be better if the controllers would either advise the flight further in advance if they're going to slow the aircraft (as this reduces the descent ability of the aircraft), or if this can't be done, cancel the crossing restriction requirement.

Original NASA ASRS Text

Title: ACR MLG ALT DEVIATION UNDERSHOT CROSSING RESTRICTION DUE SPEED RESTRICTION.

Narrative: ON DSCNT INTO DTW WERE GIVEN TO CROSS RHYME INTXN AT 8000'. THE CENTER CTLR THEN REQUESTED THE ACFT SLOW TO 250 KTS IN THE DSCNT. BECAUSE OF THE SLOWER AIRSPD DSCNT WE XED THE INTXN AND WERE LEVELING OFF JUST AT 8000' OR SLIGHTLY ABOVE. TO AVOID XING INTXNS WITH AN ALT XING RESTRICTION WITH SUCH A TIGHT MARGIN, IT WOULD BE BETTER IF THE CTLRS WOULD EITHER ADVISE THE FLT FURTHER IN ADVANCE IF THEY'RE GOING TO SLOW THE ACFT (AS THIS REDUCES THE DSCNT ABILITY OF THE ACFT), OR IF THIS CAN'T BE DONE, CANCEL THE XING RESTRICTION REQUIREMENT.

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.

Air carrier medium large transport altitude deviation undershot crossing restriction due speed restriction.