Flight crew of cpr mdt had problem with course capture of FMC during production test flight. Manufac...

Attributes
ACN	83495
Time
Date	198803
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : rzc
State Reference	AR
Altitude	msl bound lower : 40000 msl bound upper : 40000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme
Operator	general aviation : corporate
Make Model Name	Medium Transport
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 10000
ASRS Report	83495
Person 2
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance none taken : unable other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

3/88, I was cleared in a block altitude of FL390 to 410 and was flying at 40000'. The routing was multiple circuits from lit-arg-rzc-lit, etc. Approaching rzc about 30 NM east, center cleared me direct light transport. At the time I was coupled to the sperry FMC and programmed a direct to lit function. The airplane started its turn, at about a 150 degree left turn, and I then got busy with my head in the cockpit sending an EFIS message. My first realization of anything wrong was when center called with, 'I thought you were going direct to little rock.' at the time, I was heading northerly at 40000' and explained to center what had happened and asked for another 360 degree turn to see what the FMC would do when coupled to the right side flight director. The request was granted and the airplane did indeed not capture the 'direct to' leg on the right flight director. After the flight, the FMC vendor rep informed me that this was the fourth occurrence known with the new software program. Callback conversation with reporter revealed the following: reporter says he works with the FMC vendor daily and they are well aware of the problem and are working on it. Do not think ASRS could add anything to what is being done.

Original NASA ASRS Text

Title: FLT CREW OF CPR MDT HAD PROBLEM WITH COURSE CAPTURE OF FMC DURING PRODUCTION TEST FLT. MANUFACTURER SAID THIS WAS THE FOURTH OCCURRENCE USING THIS PARTICULAR PROGRAM.

Narrative: 3/88, I WAS CLRED IN A BLOCK ALT OF FL390 TO 410 AND WAS FLYING AT 40000'. THE ROUTING WAS MULTIPLE CIRCUITS FROM LIT-ARG-RZC-LIT, ETC. APCHING RZC ABOUT 30 NM E, CENTER CLRED ME DIRECT LTT. AT THE TIME I WAS COUPLED TO THE SPERRY FMC AND PROGRAMMED A DIRECT TO LIT FUNCTION. THE AIRPLANE STARTED ITS TURN, AT ABOUT A 150 DEG LEFT TURN, AND I THEN GOT BUSY WITH MY HEAD IN THE COCKPIT SENDING AN EFIS MESSAGE. MY FIRST REALIZATION OF ANYTHING WRONG WAS WHEN CENTER CALLED WITH, 'I THOUGHT YOU WERE GOING DIRECT TO LITTLE ROCK.' AT THE TIME, I WAS HDG NORTHERLY AT 40000' AND EXPLAINED TO CENTER WHAT HAD HAPPENED AND ASKED FOR ANOTHER 360 DEG TURN TO SEE WHAT THE FMC WOULD DO WHEN COUPLED TO THE RIGHT SIDE FLT DIRECTOR. THE REQUEST WAS GRANTED AND THE AIRPLANE DID INDEED NOT CAPTURE THE 'DIRECT TO' LEG ON THE RIGHT FLT DIRECTOR. AFTER THE FLT, THE FMC VENDOR REP INFORMED ME THAT THIS WAS THE FOURTH OCCURRENCE KNOWN WITH THE NEW SOFTWARE PROGRAM. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR SAYS HE WORKS WITH THE FMC VENDOR DAILY AND THEY ARE WELL AWARE OF THE PROBLEM AND ARE WORKING ON IT. DO NOT THINK ASRS COULD ADD ANYTHING TO WHAT IS BEING DONE.

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.

Flight crew of cpr mdt had problem with course capture of FMC during production test flight. Manufacturer said this was the fourth occurrence using this particular program.