Of course mobile telephones should never be used on the flight deck. Studies have shown that their signals can cause a range of problems, from interference in the cockpit and annoyance on radio communications, up to degrading the output of navigational equipment by a couple of degrees. I'm told that they can also play havoc with the service providers networks - being able to see too many base stations at once.

But what happens when your radio is unserviceable and your navigation equipment is dead? This was the challenge facing the crew of a privately-operated turboprop recently.

On March 28th a Beechcraft Super King Air 200 resident at Glasgow and operated corporately by a leading fruit and vegetable company, is reported to have suffered a complete electrical failure after departure from Glasgow bound for Conington. It was observed orbiting randomly and guided to a safe landing.

The incident is subject to an AAIB investigation, but the Scottish press reported that the aircraft had remained between cloud layers keeping in touch by mobile phone and was then intercepted by

an RAF Tornado which guided it to Leuchars after attempts to land at both Prestwick and Edinburgh were thwarted by weather conditions.

Communicating by hand signals, the Tornado crew guided the plane through clouds to safety. Flight Lieutenants Ted Threapleton and Mark Wilson, members of XXV(F) Squadron, based at RAF Leeming in North Yorkshire, were able to help the stranded aircraft because they had more fuel than usual on board.

It is almost certainly not the first time a personal mobile telephone has been used under such circumstances, so the question is; should the mobile telephone actually be considered as a last-resort emergency communi-cations channel? Should every flight carry one?

Well, if you do decide to carry your mobile with you for use in this sort of an emergency, then do take some basic precautions. Passengers on a holiday charter aircraft were recently left waiting four hours for an alternative flight at Doncaster airport after the pilot lost his mobile phone in the cockpit. Unfortunately, although the phone was switched on it was set to silent mode, and so proved difficult to locate. The aircraft could only depart after it had eventually been found, as it was considered to be a loose item

in the cockpit. As such it could have caused technical problems such as becoming stuck under flight controls, rendering them inoperable.

So, make sure you know where it is, and that it is turned off, but keep your mobile telephone handy.

You never know when you might need it!.

David Wright