A cpr captain did not arm his altitude select during descent and overshot his altitude.

Attributes
ACN	453930
Time
Date	199911
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lyh.airport
State Reference	VA
Altitude	msl bound lower : 27700 msl bound upper : 28000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc.artcc tracon : d21.tracon
Operator	general aviation : corporate
Make Model Name	Falcon 50
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 30 flight time total : 16600 flight time type : 3350
ASRS Report	453930
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : far
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

After receiving a clearance to FL280, we left our assigned altitude of FL310. During the descent, we were doing some HF radio checks, and apparently forgot to arm the altitude select mode on the flight director. As a result, we descended through our altitude. At approximately FL277 we promptly returned to FL280. As a crew, we are very diligent and disciplined about altitude assignment. But, because our attention was diverted from the task at hand, we flew through our assigned altitude. It was that classic trap of both crew members being distraction by something and no one is flying the airplane.

Original NASA ASRS Text

Title: A CPR CAPT DID NOT ARM HIS ALT SELECT DURING DSCNT AND OVERSHOT HIS ALT.

Narrative: AFTER RECEIVING A CLRNC TO FL280, WE LEFT OUR ASSIGNED ALT OF FL310. DURING THE DSCNT, WE WERE DOING SOME HF RADIO CHKS, AND APPARENTLY FORGOT TO ARM THE ALT SELECT MODE ON THE FLT DIRECTOR. AS A RESULT, WE DSNDED THROUGH OUR ALT. AT APPROX FL277 WE PROMPTLY RETURNED TO FL280. AS A CREW, WE ARE VERY DILIGENT AND DISCIPLINED ABOUT ALT ASSIGNMENT. BUT, BECAUSE OUR ATTN WAS DIVERTED FROM THE TASK AT HAND, WE FLEW THROUGH OUR ASSIGNED ALT. IT WAS THAT CLASSIC TRAP OF BOTH CREW MEMBERS BEING DISTR BY SOMETHING AND NO ONE IS FLYING THE AIRPLANE.

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.