Clearance interpretation. Missed altitude assignment account distraction from cockpit speaker.

Attributes
ACN	89063
Time
Date	198806
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sea
State Reference	WA
Altitude	msl bound lower : 4300 msl bound upper : 4500
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : sea
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 10000 flight time type : 4000
ASRS Report	89063
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	other Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Approach control issued a clearance to descend from 6000 to 2500', which was read back. Passing 4400' approach told us to level off at 4500'. We did so and asked our assigned altitude and advised that we read back 2500'. There was no reply from the controller and we were cleared for a visual approach. End of event. Cockpit communications were the worst that I have encountered, even though we both felt sure that the altitude assigned was 2500'. The captain used his overhead cockpit speaker in the medium large transport instead of a headset (normally the headset/earphone is used). His speaker is so loud that passenger halfway back in the aircraft can hear the radio communications. When the captain tunes in ATIS or company frequencys, it totally disrupts all other communications. After a 4 day trip, I honestly feel I have a hearing loss and had to ask for ATC to repeat xmissions at least 10 times/leg. Of course at the start of the trip I asked the captain to turn down his vol, which he did not. This is an accident/incident that will repeat itself many times.

Original NASA ASRS Text

Title: CLRNC INTERP. MISSED ALT ASSIGNMENT ACCOUNT DISTR FROM COCKPIT SPEAKER.

Narrative: APCH CTL ISSUED A CLRNC TO DSND FROM 6000 TO 2500', WHICH WAS READ BACK. PASSING 4400' APCH TOLD US TO LEVEL OFF AT 4500'. WE DID SO AND ASKED OUR ASSIGNED ALT AND ADVISED THAT WE READ BACK 2500'. THERE WAS NO REPLY FROM THE CTLR AND WE WERE CLRED FOR A VISUAL APCH. END OF EVENT. COCKPIT COMS WERE THE WORST THAT I HAVE ENCOUNTERED, EVEN THOUGH WE BOTH FELT SURE THAT THE ALT ASSIGNED WAS 2500'. THE CAPT USED HIS OVERHEAD COCKPIT SPEAKER IN THE MLG INSTEAD OF A HEADSET (NORMALLY THE HEADSET/EARPHONE IS USED). HIS SPEAKER IS SO LOUD THAT PAX HALFWAY BACK IN THE ACFT CAN HEAR THE RADIO COMS. WHEN THE CAPT TUNES IN ATIS OR COMPANY FREQS, IT TOTALLY DISRUPTS ALL OTHER COMS. AFTER A 4 DAY TRIP, I HONESTLY FEEL I HAVE A HEARING LOSS AND HAD TO ASK FOR ATC TO REPEAT XMISSIONS AT LEAST 10 TIMES/LEG. OF COURSE AT THE START OF THE TRIP I ASKED THE CAPT TO TURN DOWN HIS VOL, WHICH HE DID NOT. THIS IS AN ACCIDENT/INCIDENT THAT WILL REPEAT ITSELF MANY TIMES.

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.