General use of the WXR and Active Sky

[Ephedrin 418]

1 hour ago, Captain Kevin said:

That would be an unusual one if that was the case, given that commercial jets are generally flying much faster than that, and some birds fly quite high.

that was my concern too..  

[berts 97]

On 1/31/2018 at 10:13 AM, skelsey said:

Not a problem until you need wing anti-ice at which point if ATC are unobliging a Mayday may be required!

I think you actually mean a Pan call, don't you? 

Unless the Captain is a really nervous sort of guy he or she should only use a Mayday call when there is a genuine emergency. Your Leipzig info was very interesting though, because I am amazed to hear that a B744 operator expects his crews to keep the speed below 250kts and flaps out until 10,000 ft under all circumstances.  This speed would of course be OK for arrivals and departures if the aircraft was at lighter weights, because the B744 can be flown clean with the flaps up and still maintainm the speed below 250kts,  But if the aircraft was very heavy then it would definitely be a non-standard way to operate this aircraft. It looks to me as if the (legal?) tail is wagging the dog here, because the Captain is responsible for flying his aircraft safely at all times. In the latter situation I would expect the crew to advise ATC that they would be flying faster and clean (i.e.V2+100kts minimum) and even declaring a Pan if it is necessary; then argue the toss if the authorities complain later.      

Incidentally, there is no 250kt Flight Deck Window speed limitation in the AOM for a B744. However, there is a relevant limitation in the Ice and Rain section, which states that the Window Heat must be on for all flight operations.

Bertie  

[Ephedrin 418]

Concerning Frankfurt a „high speed approved“ approach or departure is actually quite common, at least for 747 and A380, not sure about other types. Though the below-250-rule in echo airspace is really strict as there are really a lot of gliders and other „weekend pilots“ around. But I have no idea about Zurich, due to the regulations with the german airspace on the one side and mountains and the city of Zürich on the other side they have strange departure routings anyway. Out of my head DEGES2 departing Rw16 is one of those..

[skelsey 765]

On 02/02/2018 at 11:23 AM, berts said:

I think you actually mean a Pan call, don't you? 

You are of course quite correct - Mayday would almost certainly be rather overstating it! 

[berts 97]

On 2/3/2018 at 11:58 PM, skelsey said:

You are of course quite correct - Mayday would almost certainly be rather overstating it! 

Thanks.  Nice to know I got something right!  Terrain clearance is the only other reason I can think of where it might be a requirement to keep the speed back and possibly have some Flap out.  Hot and high airfields like Bogota and as Marc suggests also Zurich with its high terrain, perhaps?  A pilot friend tells me Zurich had some fairly demanding SID's when he was on the B747 Classic.

Berts