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catchup
16th Jul 2004, 12:29
On A300/310 both ILS rcvrs are operated by a single control panel. A failure of the control panel therefore affects both ILS. Concerning Low vis procedures, I'm wondering how this architecture could get a airworthiness approval.

regards

Bally Heck
16th Jul 2004, 12:46
On the B757/767 all three recievers are tuned through one panel. Failure of the centre ILS will blank the panel display but the other two can still be tuned using the panel and the EHSI display.

It would be a foolish pilot who set off to a destination with forecast bad weather without fuel for an alternate with forecast good weather.

Hope that helps?

catchup
16th Jul 2004, 12:58
The point is, if you get airborne with an A300 assuming the Dep-, Dest-, and Altn-Airport has CAT1 or even worse and this panel dies, you can't bring the ship down legally.
Maybe there is an airport which can offer you a PAR appch, than you are lucky.

regards

Spitoon
16th Jul 2004, 18:45
Obvious question to ask but what other aids (that can be used for let down) are fitted? Speaking as a controller, I can usually find somewhere not far away where a NPA could be sucessfully carried out if there are real problems with an aircraft's equipment.

catchup
16th Jul 2004, 19:42
@spiton

For CATII/III there are two INDEPENDENT ILS rcvrs required. For my opinion this is for the A300 not the case. Even in CAT1 conditions I'm in trouble if this panel fails.

Sure, in an actual case there might be an airfield somewhere else than the alternate with weather at NP minimums or better, but this is just good luck, beside legal requirements.

Main systems on commercial A/C are designed double/trible INDEPENDENT , but this one is'nt for my understanding.

Regards

NSEU
17th Jul 2004, 04:04
I think you'll find that there is redundancy built into the panel. If the Airbus panel is like the 767 panel, (inside) there are separate power supplies (each of the ILS/MMR receivers can power the panel... and the receivers have separate power supplies), there are separate processors and, most likely, the switches are "ganged" (multiple contacts).

The only way you're going to get into trouble is if one of the knobs falls off ;)

Rgds.
NSEU

catchup
17th Jul 2004, 08:01
@NSEU

Concerning fallen knobs, this was actually handled quite well with a simple screwdriver. But in our fleet have been at least two cases where the panel went completely crazy. Numbers started to flash, the ILS course showed 454° and the frequency something around 300 MHZ.

BOTH ILS receivers were therefore lost. Weather was no factor in both cases.

MAYBE a disturbance by mobil telephones?

regards

catchup
5th Aug 2004, 07:41
Where are the experts for commercial aircraft certification?

regards