Air carrier medium large transport communication problem with ZHU mid gulf of mexico.

Attributes
ACN	201305
Time
Date	199201
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : gls
State Reference	TX
Altitude	msl bound lower : 35000 msl bound upper : 35000
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Controlling Facilities	tower : fpr
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : other oceanic enroute airway : a766 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 : 180 flight time total : 15200 flight time type : 4800
ASRS Report	201305
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 205 flight time total : 12000 flight time type : 4000
ASRS Report	201174
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	faa : investigated
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other
Situations
ATC Facility	other physical facility procedure or policy : unspecified

Narrative:

At nuley northbound switched to houston center as instructed by merida center. Houston center could be clearly talking to another aircraft that we could not hear. Our initial position report was unanswered. We repeated the nuley report and quickly and clearly heard 'houston center roger.' on feb/92 I received a company letter asking to confirm that the nuley position report was given since houston center did not receive the report. Houston center now has an offshore transceiver that allows aircraft to clearly hear 'their' transmission over a greater area than in the past. Apparently their ability to receive is not equal. Also houston center usually has 1 controller working the offshore as well as the coastal high sectors. Neither airborne aircraft can hear the other. Because of different frequencys, but all of the controllers xmissions are simultaneously transmitted on both frequencys. If both aircraft transmit at the same time, houston could possibly only hear the close to shore aircraft. When the reply is transmitted on 2 separate frequencys, both aircraft believe their report has been received especially if the reply is 'houston center roger.' to correct the problem houston center needs to insure that the offshore sector's ability to receive xmissions is equal to its ability to transmit. Secondly, and ideally once they have the 2 way capability have just 1 controller working 1 sector, eliminating the dual frequency transmission that can be misconstrued by other aircraft. Supplemental information from acn 201174: after second position report to houston at nuley intersection heard a 'roger, 'houston center.'

Original NASA ASRS Text

Title: ACR MLG COM PROBLEM WITH ZHU MID GULF OF MEXICO.

Narrative: AT NULEY NBOUND SWITCHED TO HOUSTON CTR AS INSTRUCTED BY MERIDA CTR. HOUSTON CTR COULD BE CLRLY TALKING TO ANOTHER ACFT THAT WE COULD NOT HEAR. OUR INITIAL POS RPT WAS UNANSWERED. WE REPEATED THE NULEY RPT AND QUICKLY AND CLRLY HEARD 'HOUSTON CTR ROGER.' ON FEB/92 I RECEIVED A COMPANY LETTER ASKING TO CONFIRM THAT THE NULEY POS RPT WAS GIVEN SINCE HOUSTON CTR DID NOT RECEIVE THE RPT. HOUSTON CTR NOW HAS AN OFFSHORE TRANSCEIVER THAT ALLOWS ACFT TO CLRLY HEAR 'THEIR' XMISSION OVER A GREATER AREA THAN IN THE PAST. APPARENTLY THEIR ABILITY TO RECEIVE IS NOT EQUAL. ALSO HOUSTON CTR USUALLY HAS 1 CTLR WORKING THE OFFSHORE AS WELL AS THE COASTAL HIGH SECTORS. NEITHER AIRBORNE ACFT CAN HEAR THE OTHER. BECAUSE OF DIFFERENT FREQS, BUT ALL OF THE CTLRS XMISSIONS ARE SIMULTANEOUSLY XMITTED ON BOTH FREQS. IF BOTH ACFT XMIT AT THE SAME TIME, HOUSTON COULD POSSIBLY ONLY HEAR THE CLOSE TO SHORE ACFT. WHEN THE REPLY IS XMITTED ON 2 SEPARATE FREQS, BOTH ACFT BELIEVE THEIR RPT HAS BEEN RECEIVED ESPECIALLY IF THE REPLY IS 'HOUSTON CTR ROGER.' TO CORRECT THE PROBLEM HOUSTON CTR NEEDS TO INSURE THAT THE OFFSHORE SECTOR'S ABILITY TO RECEIVE XMISSIONS IS EQUAL TO ITS ABILITY TO XMIT. SECONDLY, AND IDEALLY ONCE THEY HAVE THE 2 WAY CAPABILITY HAVE JUST 1 CTLR WORKING 1 SECTOR, ELIMINATING THE DUAL FREQ XMISSION THAT CAN BE MISCONSTRUED BY OTHER ACFT. SUPPLEMENTAL INFO FROM ACN 201174: AFTER SECOND POS RPT TO HOUSTON AT NULEY INTXN HEARD A 'ROGER, 'HOUSTON CTR.'

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.