Cargo DC8 descends below assigned altitude.

Attributes
ACN	319351
Time
Date	199511
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : jfk
State Reference	NY
Altitude	msl bound lower : 22500 msl bound upper : 23000
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Controlling Facilities	artcc : zny tracon : cmh
Operator	common carrier : air carrier
Make Model Name	DC-8 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	arrival other arrival star : star enroute other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 4500 flight time type : 3000
ASRS Report	319351
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot non adherence : clearance
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During a clearance to FL230 on the lendy 4 arrival, inadvertently descended to FL224 before realizing altitude bust. Autoplt was flying descent (500-1000 FPM). Callout had been made by first officer when at FL240. First officer also missed going through FL230. Altitude alerter was operative and did sound off at FL225. Initiated an immediate climb to FL230. ZNY called to confirm altitude cleared to and then cleared us to FL190. We thought he had already cleared us to FL190. Contributing factor to this incident was some mechanical problems with aircraft during this flight. During flight from cvg, we had 2 problems develop. First was the first officer's pitot system froze rendering his airspeed inoperative. Secondly, the captain's windshield began to arc at FL330 and ended up having the outer pane shatter during flight! Definitely the maintenance problems with aircraft coupled with early morning flight (being on duty all night) diverted the crew's attention to monitor the altitude cleared to! Should make altitude awareness paramount!

Original NASA ASRS Text

Title: CARGO DC8 DSNDS BELOW ASSIGNED ALT.

Narrative: DURING A CLRNC TO FL230 ON THE LENDY 4 ARR, INADVERTENTLY DSNDED TO FL224 BEFORE REALIZING ALT BUST. AUTOPLT WAS FLYING DSCNT (500-1000 FPM). CALLOUT HAD BEEN MADE BY FO WHEN AT FL240. FO ALSO MISSED GOING THROUGH FL230. ALT ALERTER WAS OPERATIVE AND DID SOUND OFF AT FL225. INITIATED AN IMMEDIATE CLB TO FL230. ZNY CALLED TO CONFIRM ALT CLRED TO AND THEN CLRED US TO FL190. WE THOUGHT HE HAD ALREADY CLRED US TO FL190. CONTRIBUTING FACTOR TO THIS INCIDENT WAS SOME MECHANICAL PROBS WITH ACFT DURING THIS FLT. DURING FLT FROM CVG, WE HAD 2 PROBS DEVELOP. FIRST WAS THE FO'S PITOT SYS FROZE RENDERING HIS AIRSPD INOP. SECONDLY, THE CAPT'S WINDSHIELD BEGAN TO ARC AT FL330 AND ENDED UP HAVING THE OUTER PANE SHATTER DURING FLT! DEFINITELY THE MAINT PROBS WITH ACFT COUPLED WITH EARLY MORNING FLT (BEING ON DUTY ALL NIGHT) DIVERTED THE CREW'S ATTN TO MONITOR THE ALT CLRED TO! SHOULD MAKE ALT AWARENESS PARAMOUNT!

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.