RAIM is baro-aiding and works (in general) only if you are receiving only (IIRC) 3 satellites. If you are receiving "loads" then it doesn't do anything.

If they jam GPS then London will be jammed with lost drivers... that really will be fun.

One should not equate a lack of "gadget proficiency" with the use of GPS. You can suffer from the former with any piece of nontrivial avionics, if you don't read the manual and/or try to do something odd during the flight.

The wording is daft.

If they complained about "over-reliance on a single means of navigation" it would make more sense.

Taking any two out of map-crawling, VORs, NDBs, GPS and DR should allow the basic cross-checking you need for safe navigation. I can't understand why they single out GPS. Perhaps pilots over-rely on GPS more than the other things, but the error is to over-rely on any single thing.

Peter, didn't you learn anything trudging through the IR TK? ;)

It's a minimum of five satellites for a 3D fix and RAIM, six with the above and FDE.

Oh well there you are :)

I did that stuff a year ago... Although without looking it up in the KLN94 manual I wouldnt be too sure.

Just read the Clued Up mag article. That comment is just a bit of a throwaway remark, out of surrounding context. Stupid all the same. Even NATS, fed up with hundreds of major CAS busts a year, sponsored that £150 GPS box...

GPS can be used for lots of legitimate functions. However it can also be used to guide things which might have more sinister intent. Remove the GPS or spoof its position and then you have plugged one hole. WHO cares about a driver getting lost, pilots are being warned to not be over reliant upon it. READ between the lines with respect to the Olympic months, it's not something that takes a rocket scientist to work out.

From a notam a few weeks ago (Plot the Arc out and see the extents)Peter - in the past you have argued it could not happen and would not be allowed to happen, it has and I suspect during the Olympic period will be used at random times and possibly (due to operational neccesity) will be deployed without warning

Last week there was a trial which radiated 75nm radius from Sennybridge...

GPS spoofing was the claimed method of interception of an American UAV last year - it went into landing mode because it thought it was 2000nm from its true position and was back at its home base and thus entered autonimous recovery mode (no pilot intervention)

Not far off getting an iPad with Sky Demon (funds permitting)... but..

If I'm VFR I will still look out of the window and apart from looking for traffic will check that I am where I think I am from time to time..

If I'm IFR I will still have all the boxes on, tuned, idented and check that what they are telling me agrees with the GPS

If there seems to be a disagreement then I'll do something about it!

Why would I not use all of the information I have available?

Don't banks make use of GPS to timestamp transactions? I wonder if the jamming will affect payment systems?

Of course, I am sure every UK bank has taken the proper precautions.

:E

Meldex

ONLY via NOTAMS....... how much more official would you like, I presume you are not a pilot so do not understand the notam system?

If I may presume to say so, I think that Meldex may be asking whether there has been any "general" pre-notam indication that GPS jamming will take place. I have not personally heard of any statements of that nature, and the effects of it anywhere near the restricted or prohibited zones would, I would have thought, led to infringement armageddon and carnage and aircraft wreckage all over the streets of London.

That would be quite clever since the UAV would be using military encrypted GPS signals... not the civilian signals.

I think the AAIB is infected with the same attitude against GPS as some in the CAA. Old retired airline pilots and ex Military navigators, with little operational knowledge of the subject.
Personally I would not stray far from my base in the London area without GPS, in anything other than good VMC, for the enhanced situational awareness it gives.
The recent advent of cheap, IPad based, GPS moving map displays is one of the greatest navigation airsafety advances in recent years.

Thats quite an assumption Peter!!!

Can you tell us the actual details of the incident? To be helpful I will give you a clue, the UAV was not using M code data at the time of the incident.

We have touched some precious GPS nerves... I'll add some more petrol. GPS should be banned from light aircraft. A chart, clock and pencil is all that is required. Enhanced situational awareness - spare me! That's what the chart is for - and it doesn't require power. Just fly the (sensible) heading and time and you won't be far off.

They bloody well are. When GPS first came out in the UK, it didn't take long for the first victims to arrive. I've shepherded a few out of the Luton zone when I was flying a tug out of LCG at Dunstable. One was due to flat batteries, the other was finger trouble. Both had charts and working radios, but wasn't enough for these two.

PM

Evidently whoever wrote that one-liner is, but I would have seriously thought that the old guard would have moved on by now, retiring to their rightful fine china teacups at the Royal Institute of Navigation.

Let's face it - they must get more than adequate exposure to modern avionics in the wreckage which they pull the remains out of. They must wonder what all those LCD displays are showing.

Absolutely so.

If one wanted to be useful one could say that a route should be planned as far as possible to be VOR/DME-navigable, flown 100% using a GPS, and then you have an instant drop-down backup. That is what I do when flying VFR (though often a VOR-radial route is not viable). But PPL training isn't like that. It is possible that a good IMCR instructor might suggest to a new IMCR holder that from now on, every flight is planned as "IFR"; that was suggested to me in 2002 and it's obviously a great idea.

I don't think so. Bank transactions are generally handled by (or through?) computers, computers generally get their date and time information through an internet protocol called NTP. True, some NTP servers use GPS receivers as their source of information, but some are far away and some do not use GPS at all, like caesium clocks. And yes, these protocols do know how to deal with propagation delays.

The AAIB and the CAA do actually have a point and they are NOT blamimg the spanner they are criticising the mechanic.

We have seen lots of people with road based GPS being "over reliant "or following it blindly resulting in cars in rivers, trucks where no truck should be and the like.

Airborne GPS is no different. If you follow the magenta line and have no idea where you are or what the surrounding terrain and airspace is like then you are a plonker.

That's true but driving is not a comparable situation to flying, for a whole pile of fairly obvious reasons. On the road, take your eyes off the road for a few seconds and you may be dead. The whole scenario is different. And yes a % of drivers are truly completely stupid and some evidently will drive a car into a river. But given the crap databases of many driving units, one can easily get led down the wrong street and then you get some d1ck who is tailgating you who knows the area well getting all hot under the collar :) Satnav is actually really crap; the other week I was in a hire car in Germany, in close to zero vis due to heavy rain, and the satnav just kept taking us back to the same road which was closed due to roadworks. Obviously the locals behind us were going nuts... I am sure every driver can relate to that. Serious commercial travellers have high-end solutions for that kind of thing and they aren't cheap. I was lucky; I had a passenger who was able to work out how to work the satnav.

There are certain specific things which are less than smart to be doing with an aviation GPS e.g. entering waypoint coordinates using lat/long numbers, or using user waypoints in a unit which is in a shared aircraft ;)

But any GPS with a moving map that depicts the general area makes it awfully hard to get lost.

OTOH the other day I did a search on Ebay for used Pooleys Guides (just as a joke, for a presentation I was doing, where I wanted to make a point about flying with current data) and I counted 17 of them, mostly several years old (which translates to several hundred UK PPLs flying with massively out of date Pooleys i.e. a few % of the pilot population) so I suppose there are people out there stupid enough to fly with a £50 GPS from Millets which gives you zero situational awareness.

In that case the issue isn't the GPS (which is prob99.99999 doing its job) but you just have a pretty good proof that common sense is not a requirement for getting a PPL.

I always tell people to buy a nice big GPS, not the little ones. With a decent big GPS it is virtually impossible to get lost.

But the whole training environment is pretty poor and carries on being pretty poor, and not everybody has the benefit of knowing somebody who can provide a bit of mentoring. When I did my IMCR (2002) we used 2 planes, both PA28s, one with a working ADF but a duff DME and the other with a good DME and a duff ADF. The instructor (a CPL/IR who later got a job flying commuter turboprops) was ever so proud of his £50 GPS which he got in the USA for £20 less than they were in the UK (and he told everybody about that) set the airport as a DCT and used the GPS as a "DME" and read out the numbers to me when I was learning NDB approaches. What is the moral of the story? In 2012, such a student should perhaps ask his school for a 50% refund :E

Loads of easy ammo for those looking for an example.

What they forget is that if you get the proverbial interview at Gatwick without tea and biscuits, they won't give you any credit for pulling out a CRAP-1 and a beautiful handwritten plog.

????

My homebrew gps has ALL its waypoints defined as lat/long numbers and seems to work pretty fine. Or have I just been lucky to get to my VRP's and destinations time and again?

Come to think of it, what other better way is there to define waypoint coordinates, besides lat/long numbers?

Buy a GPS with the waypoints in the database.

The only time I have used user defined waypoints for enroute data was in 2003 for the position of LEAX.

And how would you think the waypoints are defined in the database? Lat/long numbers, any chance? Or do you imply a database one paid for is more reliable because of the amount one paid for it? I'am afraid I am missing something somewhere.