Westland Lynx

[j.ketelings]

Hi,

My first post here. Maybe someone knows answer.

At our school (Aviation Competence Centre) we recently received a Lynx helicopter from the royal dutch navy.

Unfortunately nobody at our school has any knowledge about this helicopter yet,
so no one knows the solution.

Our problem,

When switching on the V/UHF radio or even the UHF radio we can receive transmissions from the airport (EHBK) but these transmissions are with a lot of noise where the reception of our F-16 aircraft in the same building is al lot better.

Then when we press the PTT switches a loud beep tone is heared through the headsets.

This beeptone is heard on all frequencies.

We also have no intercom functionality as we can not hear each other talk.

We tried to communicate between the F-16 and Lynx and in the F-16 I could hear the beeptone from the Lynx on the radio. So we know the Lynx transmits but its not our voice but only a beep tone (almost like a morse code tone).

I read in the manuals that the Lynx requires a specific headset jack plug. Currently we use a heaset with U-174/U.

When the radio is put in testmode 888888 is shown.

So if anyone knows what the problem might be?
We would be very thankful.

Regards,
Jeffrey Ketelings

[Sketretal]

Is there a seperate controller for secure speech? It might be switched on inadvertently.

[tucumseh]

Further to sketretal, is it likely that the donor of the aircraft would remove any secure speech system? I have no idea what systems are fitted to Netherlands' Lynx, but in the UK the secure speech is (or was) an overlay on the older clear intercom. Clear was an SG Brown system, Secure a GEC/Marconi. Ripping out the secure speech components would mean the remainder could not be expected to function properly. Here, in the same circumstances, the "secure" part would be removed, but you would be left with components of the clear system that had been modified to anticipate certain interfaces and interlocks.

If the Netherlands use a specific intercom jack, then you may find Tels is connected, but Mic isn't, which would explain some of your problems. In modern (post mid-90s) systems, you may find the Mic/Tels connector doubles as ANR power, in which case yes, the connector must be selected and wired so certain contacts make and break before the others.

Beep is a function of an LRU, not Mic, so it isn't a contradiction to have one and not the other. You may find the Mic Amps and headsets are mismatched.

Sorry, not a lot I can say without schematics. But start at the beginning and use a helmet/mic specified for use in that aircraft.

[j.ketelings]

Thank you very much for the information.

We will try to get the proper headsets and I will report our findings.

Regards,

Jeffrey

[MOSTAFA]

My time on Lynx 2000 hrs is a wee while ago and a great many aircraft have gone in between but I seem to remember an upper and lower antennae switch somewhere - just maybe?

[Shawn Coyle]

The 'beeptone' will probably be a low rotor RPM warning, which should be capable of being disabled - it's been way too long since I flew a Lynx, so I don't remember which switch it might be... But I do remember it was quite loud and alarming!

[j.ketelings]

The problem is solved.

It was indeed the wrong headset. I changed the wiring in the helicopter to fit our "US nato jack plug" from the headsets.

thanks to all for trying to help!

Regards,
Jeffrey