During maintenance flight, flight crew of B737-400 lost communication with ATC after missed approach at destination. Returned to departure airport and landed using light signals.

Home

Browse by month

Random

Latest

About

Contact

Attributes
ACN	574029
Time
Date	200302
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sea.airport
State Reference	WA
Altitude	msl single value : 6000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : s46.tracon tower : sea.tower tower : pae.tower
Operator	common carrier : air carrier
Make Model Name	B737-400
Operating Under FAR Part	Part 121
Flight Phase	landing : missed approach
Route In Use	arrival other enroute : on vectors enroute other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	574029
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : vhf comm radios intermittent other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance controller : provided flight assist flight crew : diverted to another airport flight crew : landed in emergency condition other
Consequence	other other
Supplementary
Problem Areas	Aircraft Weather
Primary Problem	Aircraft

Narrative:

After requesting a missed approach from sea tower to work out a duct pressure problem, we were given a climb to 5000 ft on runway heading. We then contacted sea departure on 120.4 and were given a right turn to 210 degrees and a climb to 6000 ft and asked our intentions. We replied we would like a vector out to the west to investigate our problem and contact our maintenance personnel. Shortly thereafter, we began having difficulty with both of our VHF radios and had intermittent contact with departure control. We tried an alternate frequency and had the same result. We squawked 7600 and began trying other means of establishing contact. Eventually, we were able to get an approach clearance from ZSE on 128.5 for approach to pae field, our departure airport. We were unable to contact pae tower on VHF and were given landing clearance by light signal. Supplemental information from acn 574030: after landing and block-in, called pae tower on the phone and they advised that we were still transmitting on tower frequency. Later, calls to sea approach and center said that we were blocking their radios as well. Maintenance suspects reu.

Original NASA ASRS Text

Title: DURING MAINT FLT, FLT CREW OF B737-400 LOST COM WITH ATC AFTER MISSED APCH AT DEST. RETURNED TO DEP ARPT AND LANDED USING LIGHT SIGNALS.

Narrative: AFTER REQUESTING A MISSED APCH FROM SEA TWR TO WORK OUT A DUCT PRESSURE PROB, WE WERE GIVEN A CLB TO 5000 FT ON RWY HDG. WE THEN CONTACTED SEA DEP ON 120.4 AND WERE GIVEN A R TURN TO 210 DEGS AND A CLB TO 6000 FT AND ASKED OUR INTENTIONS. WE REPLIED WE WOULD LIKE A VECTOR OUT TO THE W TO INVESTIGATE OUR PROB AND CONTACT OUR MAINT PERSONNEL. SHORTLY THEREAFTER, WE BEGAN HAVING DIFFICULTY WITH BOTH OF OUR VHF RADIOS AND HAD INTERMITTENT CONTACT WITH DEP CTL. WE TRIED AN ALTERNATE FREQ AND HAD THE SAME RESULT. WE SQUAWKED 7600 AND BEGAN TRYING OTHER MEANS OF ESTABLISHING CONTACT. EVENTUALLY, WE WERE ABLE TO GET AN APCH CLRNC FROM ZSE ON 128.5 FOR APCH TO PAE FIELD, OUR DEP ARPT. WE WERE UNABLE TO CONTACT PAE TWR ON VHF AND WERE GIVEN LNDG CLRNC BY LIGHT SIGNAL. SUPPLEMENTAL INFO FROM ACN 574030: AFTER LNDG AND BLOCK-IN, CALLED PAE TWR ON THE PHONE AND THEY ADVISED THAT WE WERE STILL XMITTING ON TWR FREQ. LATER, CALLS TO SEA APCH AND CTR SAID THAT WE WERE BLOCKING THEIR RADIOS AS WELL. MAINT SUSPECTS REU.

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.