[James Chan]

one of the greatest on board resources is the Mk1 eyeball and a map.

My on-board instruments trumps that. Sorry!

[Harry Brown]

Your never lost until the circle of uncertainty is larger than the map you are carrying

[PaulB]

Your never lost until the circle of uncertainty is larger than the map you are carrying

I think I'm going to ignore Mr Brown as I think he's taking the pi$$

[Dave Phillips]

GrahamB, I think the problem was actually how to promulgate the actual QNH for reference airfields within an ASR.

That may have been their problem, but the whole concept of RPS for GA is flawed, and would be made worse by fewer of them. IMHO, of course.

Read the CAP. They were talking about getting rid of RPS and using actual QNH.

[GrahamB]

GrahamB, I think the problem was actually how to promulgate the actual QNH for reference airfields within an ASR.

That may have been their problem, but the whole concept of RPS for GA is flawed, and would be made worse by fewer of them. IMHO, of course.

Read the CAP. They were talking about getting rid of RPS and using actual QNH.

OK, thanks, I'd got the wrong end of the stick. That's an improvement over using a forecast lowest figure, but I still don't see why one needs a single promulgated QNH across a wide area at all.

[Dave Phillips]

How else do you fly underneath a TMA which has a common 'wide-area' QNH? For example, the London TMA is based on Heathrow QNH, it doesn't hop between the various London airports.

[Oldfart]

Why would you ever use the RPS? Except perhaps in the wilds of Scotland, you are always in VHF reception of the up to date accurate local QNH.
Like wat they do in USA to 18000ft. for many years, safely.
If we ever raise our archaic TL to sensible heights, I hope we don't use RPS then!

[GrahamB]

How else do you fly underneath a TMA which has a common 'wide-area' QNH? For example, the London TMA is based on Heathrow QNH, it doesn't hop between the various London airports.

Of course it makes sense under a single TMA/CAS structure, we're all used to using a London QNH as things stand now. Extending the concept to areas where there is no CAS with a floor under the TA is what I'm questioning.

Training pilots to routinely ask for an RPS/RQNH whenever they are en-route, irrespective of route, seems a daft thing to do. Training pilots to think about which QNH values they will use and where/when they will get that information, as part of flight planning seem a more sensible.

[xtophe]

Training pilots to routinely ask for an RPS/RQNH whenever they are en-route, irrespective of route, seems a daft thing to do. Training pilots to think about which QNH values they will use and where/when they will get that information, as part of flight planning seem a more sensible.

Training pilots do what they instructors taught them.
My view is that the only time you should be proactively finding a QNH is when approaching CAS or when landing at an unmanned airfield.

At all the other time, you get it from whoever you speak to / listen out on the radio or ATIS.

You cannot go that far or that long between meeting CAS or having to speak to someone and so the little inaccuracy between your set QNH and the actual wouldn't matter.

[mo0g]

Another reason for using listening squawks I guess, can pick up the current QNH and any changes to it.

If you are flying across a front it might be worth proactively asking or listening for it, at least.

[Harry Brown]

Can someone explain this to me please?

See Paul Bertorelli for details.

Well done Paul at least someone has a sense of humour. On a more serious note extending outside of the normal circuit pattern can cause enormous problems in a busy ATZ.

I stopped sending students to one particular airfield because this practice was putting them over a town with nowhere to go if the engine stopped

[Harry Brown]

one of the greatest on board resources is the Mk1 eyeball and a map.

My on-board instruments trumps that. Sorry!

Dont be sorry James but if you have discovered an instrument that out "Trumps" a human eye could we become friends because I think you are going to become incredibly rich

[johnm]

Dont be sorry James but if you have discovered an instrument that out "Trumps" a human eye could we become friends because I think you are going to become incredibly rich

In my case much of my flying is IFR and dead reckoning and eyeball are completely useless, except the eyeball is a help in scanning the instruments.

If flying VFR I use the same approach but it’s now worth looking out of the window for traffic and scenery.

[Harry Brown]

and are most CA infringements conducted under VFR or IFR?

[PaulB]

and are most CA infringements conducted under VFR or IFR?

Oh, come on... is most (of our type of flying) VFR or IFR?

Damn!