There is a problem with cover in the North Sea Offshore sector RTF due to a combination of extreme range and coverage gaps in the REBROS system. The worst offender seems to be on 131.3 (Sumburgh Radar) as aircraft in the Beryl area are at the extremes of RT cover. The REBROS system (Aberdeen Information) does have "black holes" on the 048 HMR between 80 and 90 miles and further south between the western edges of coverage of the Fulmar and Forties transmitters.
As Data Dad has said these problems are well known and are being addressed, however those who control the purse also control the solution to our problems.
The seemingly good cover at extreme ranges can sometimes be due to Tropo Ducting...a phenomenon of High Pressure systems.
Do however note that the Scottish transmitters are located at Sumburgh and Windy Head (where one of the 134.1 transmitters is located)...so you are often right on the limits of their RT cover too!
We are aware that using "Test" is a pain and is noisy, but a bit of noise and relevant traffic info is surely better that climbing into the unknown. Controllers try to address the RT problems of a/c descending in field by asking for a check passing through a specific level. This is to ensure we don't lose two way before you have transferred your flight watch.
Why not pop across to the tower one day and have a look around. We do have quite a fetching chart of the offshore area showing theoretical RTF cover for Aberdeen Info at 1500 feet, and you can listen in to the freqs and get an idea of where the trouble spots are!
Please bear with us...we get as frustrated as you do!!
