Helicopters over london

[davethelimey]

Feel free to hoof this off to somewhere else but:

All this hoohah about whether a single engine prop can glide clear of civilisation in the event of an engine failure is interesting, but as far as I'm aware a helicopter with an engine failure will have difficulty doing anything other than plummeting.

Are helicopters that much more reliable than props that they don't need the rule?

[Jerricho]

Trying to recall in my beer fuddled brain, but there are certain areas of London where only twin engined helicopters can fly direct and not on the designated helicopter routes.

[GT3]

ditto (beer fuddled) and ditto (the specified area i think)

[Pub User]

Dave

Plummetting is not quite correct, but the 'glide' angle of an autorotating helicopter is considerably steeper than that of an aeroplane.

Conversely, the space required for a helicopter to land after an autorotative descent is much smaller than that required by an aeroplane. The helicopter pilot can flare off almost all of the forward speed before touching down.

The 'specified area' of central London has designated routes for single-engined helicopters, which keeps them over areas judged to be suitable for an autorotative landing, without overly endangering those on the ground. Practically speaking this means that helicopters flying over the very centre of London have to fly along the Thames, and in the event of an engine failure are obliged to ditch in the river.

[headsethair]

Misunderstanding persists. ALL helis have to be able to land without endangering life or property in the event of an emergency. The "glide clear" is not a requirement for helis. That's for planks.
And the majority of inflight emergencies happen to twins. See quarterly CHIRP publication by CAA.

[ATCO Two]

Pub User,

According to the Amendment to Rule 5, as from 1st April 2005 the Specified Area over Central London no longer exists.

Further to my last, we are seeking clarification about the Specified Area over Central London. The reference may just have been moved to the ANO (CAP 393) Section 5.

[effortless]

Not a rotorhead myself but when Sussex police changed their mount some years ago I was told that it was because that single engined helos were restricted to higher altitude over built up areas. Not v. effective for chav chasing.

[ATCO Two]

OK, I can confirm that the Specified Area over Central London will continue to exist in its present form. The only change is that the reference to it will move to CAP 393 (Air Navigation Order) Section 5.