ILS (Is Last Sentry) :)
So what you suggest would not be legal IMHO.
That’s correct 
You just cannot beat an ILS
Peter wrote:
You can fly GPS/LNAV (i.e. not LPV) approaches using user waypoints.
Not according to any AFMS I have read. The entire approach must be loaded from the database as an approach. So what you suggest would not be legal IMHO.
Peter, I agree.
Thee point I am trying to make is that if you have to divert to somewhere unfamiliar, maybe due to weather, fuel or an aircraft problem….then a map (for runway elevation and terrain), an ILS frequency and a QDM is all you need.
Some sort of radar service would be nice too.
You can fly GPS/LNAV (i.e. not LPV) approaches using user waypoints. Just make sure you load them correctly and test the finished job in VMC And you won’t get the automatic scale tightening from 5 to 1 to 0.3nm but you can do that manually.
There is no way to achieve LPV that way, although there is no reason why an “LPV GPS” could not be implemented on a phone or a tablet.
the aircraft I fly day to day is one of the most advanced technologically..but doesn’t have SBAAS capability. So it is certainly a nice to have as opposed to a necessity.
@Teal what you may be referring to is this. That is why even in an uncertified aircraft you probably want to install a certified GPS.
That’s unless you are an airline pilot in which case it may be true also
Interesting thread, that I have only just managed to catch up on and I have learned a lot from.
One thing that I think is worth remembering is that although PBN approaches can appear to be the saviour, they are useless if you don’t have the approaches in “the box”. It is easy to get oneself into a false sense of security, whereby you can think you can do a PBN approach anywhere and it is your get out of jail card.
Though it is compelling to get into the vagueries of flying smooth arcs and holds, in extremis, all you need is to find an approach to precision minima. With an ILS you don’t need the coded approach but just a frequency and a QDM. As long as you know the airfield elevation and have a reasonable idea of terrain you could fly it without an approach plate. Whilst this is not ideal or legal it might be all that you have.
Interestingly, the aircraft I fly day to day is one of the most advanced technologically..but doesn’t have SBAAS capability. So it is certainly a nice to have as opposed to a necessity.
Rgds
Peter, thanks for the pointer to that thread. My guess is that if anyone knows about this stuff it will be @NCYankee, who has a similar GPS and AP setup in his Bo.
Alex, interesting that it’s not just Maules which are affected, so it’s nothing to do with the roll servo operating on the rudder instead of the ailerons (which are more or less only for “show” on a Maule). Knowing of this “fault” (I guess Microsoft would call it a “feature”), I guess we could help the AP roll into the turn by giving the control wheel a tweak (or the rudder in your case), but that rather defeats the point of running an autopilot.
Cobalt, good point, there might have been a wee bit of south easterly, but I’m sure it wasn’t much – we don’t really get wind in Scotland (outside of the Holyrood parliament building). I’ll download and check the ground speed from the engine monitor. OSMEG is a convenient local waypoint from which to start a practice GPS cloudbreak over Loch Ken. Perhaps I should ask NATS to add the others – and while theyre at it, to move JACKO up here from the Thames estuary.
Quite a bit of Easterly wind, perhaps?
If so, that would be explained by the AP not correcting the anticipation for wind. Which it could, in principle, but maybe doesn’t
On a less serious note – where is the waypoint OSMEG? And are there any called LISTR, RIMMR, DECAT and HOLLY in the vicinity? Just wondering…
I don’t think there is a “fix”. You would need a completely different algorithm for implementing turns.
Jacko wrote:
Of course, a couple of hundred yards overshoot doesn’t matter in practice, but it looks a bit sloppy to anyone watching a radar screen. I would hate ATC to think that any Maule pilot would be so busy drinking beer as to fly a procedure like that.
The citation mustang often overshot regardless of beer consumption so I wouldn’t worry about it.
