In terms of risk management / quality control, yes, obviously, exactly that.

Is there such a thing as 'military GPS signals'? I had understood that civilian and military GPS was the same ever since the DoD switched off Selective Availability in 2000.

There is still a mil frequency which they use in conjunction with the civi one.

The civilain freq used to have a fudge factor built into it which knocked the timing off so it wasn't as accruate as the mil one. They can also switch it off if they so desire and leave the mil one on.

Entering waypoints on a moving map GPS is a simple matter of clicking the mouse or pressing the screen at the appropriate point. The way point must then be in the correct place on the route and map. If in doubt do a "simulated" flight of the route. Entering multiple digits and setting off blind and hoping for the best is simply asking for trouble. Reminds me of one time I entered "Bangor" into a route simply using a stored database of towns in the GPS. This was on a flight to Caernarfon in North Wales. I spotted that something might be wrong when it tried sending me off across the Irish Sea to Bangor in Northern Ireland. Someone later remarked that I was lucky not to have ended up in Bangor Maine in Canada (or wherever it is.)
If you can see the route on a map before you set off you can't
really go wrong.

MJ

Ten years ago you would have been right - now (roughly)three modes L, P or M, the L is roughly the old military standard of ten years ago, typical accuracy with 6 sats is about +/- 300mm (dependent on RX)

P is an encrypted signal version of L and more resiliant to blocking

M is much more complicated and from 2013 will become even better due to the deployment of beamed signals to a specific area.

L is what civilian aircraft use.

What is L2?

L2 - a second frequency that can either be used alone (L2C) or in conjunction with the L1 frequency (often refered to as the coarse date frequency) to improve the overall accuracy of "L" for civilian use, which places the equipment outside the Wassenhar agreement for dual use technology

The mil encypted was always on a seperate frequency.

They did actually use the civi one as well to be able to adjust out atmospheric effects.


Mind you my knowledge is from being constripted due to knowledge of newtons laws and pocessing a scientific calculator on a gun position to the command post when the lay computer went tits up.

SMIG Badger Finnch and BSM Murphy I think there names were, after the intial "I don't care if your a sapper son" followed by a belt round the head with an A4 binder gave me a crash course in position fixing, firing out the errors, cresting and other such gun bunny perversions. Easy week with a rover full of survey gear out the window. Swapped for "confirm" "confirm" "down safety" "No 1 gun, 5 rounds fire for effect down safety fire!!" noisy bastards.

L2 is 1227.60 MHz as opposed to L1 at 1575.42 MHz. Latest satellites will transmit both frequencies and allow a civil dual frequency receiver to correct for ionospheric delay, the largest source of error, without needing to rely on the WAAS signals.

We are going all techie on here - my crayons are struggling to keep up!!

Fair enough.

As I said I was conscripted due breaking the number two rule of letting on that you know something. They had been given doppler velocity measuring things for the guns and a drinking mate was a number one. Him being a gun bunny was thick, so I was explaining how doppler worked and how that if you had the speed you could relatively easily work out the fall of shot. Someone overheard and grassed me up.

Did the conversation go something along the lines of "you horrible little man, pin your ears back and remember I am your God and your father - now keep your mouth shut. 50 press ups on the spot!!"?

Gun Bunny's are as bad as Rock Apes, in fact they are just a genetic mutation of each other.

Saying that modern Rock Apes do a fantastic job as QRF

PS: My brother in law was a Rock Ape as part of a QRF - disgusting to go out with them for a drink!!

Nah its wasn't to bad, in fact after the second day when some stupid tart managed to burn out the alternator on the coms wagon "the belt was making an awfull noise so I tightened it" and then killed the batteries and I butchered a 4 tonner to get things going again. OC "Young man is that authorised" BSM "yes sir by me" Got one of the plant fitters from the tankies to drop one off and a tool box inside an hour and had it fixed between fire missions. The SMIG stopped the bollocking for getting oil on the mission sheets.

After that I had access to the BSM's private store of Brown Ale, bastard though wouldn't let me have the rugby on the radio though. Missed one of the rare Scottish victorys over England at Twickenham.

I was excempt from that running round the gun bollocks. Did have a shot of being number three though when on the last day the special battery/thing turned up. Which earned me a burnt boot toe cap and another belt round the ear for trying to see how much flame I could get out the back of the gun by releasing the breech at the back of the recoil.

The burning of the charge bags with the BSM was top fun as well.

So in the end a not to bad exercise. The other lads who went to Otterburn came back with trench foot and a sense of humour crisis.

What was the number one rule?

Never volunteer for anything.

This is vitally important when there is "otterburn" being mentioned anywhere in the building. Just typing the word makes me feel cold, wet and pissed off, makes Dartmoor feel tropical.

I was quite surprised to see this comment in Clued Up as I read the AAIB report every month but I don't remember ever seeing "overuse of GPS" mentioned as a factor in any accident.

At first I thought Sir Niall was confusing the date with April 1st. Had to check my copy of Clued Up first and yes, there it is.

Unbelievable.

I don't think I have ever read anything as idiotic about aviation as this comment.

Poor situational awareness is due to GPS? In which cave and which century do these people live? The REALLY scary thing about this comment is that it comes from someone professionally involved in aviation.

:ugh:

Have you noticed how many thread wanderings are started by some of the more senior (ahem) forumites? :hmm:

Pressing GoTo for the OP here's another thing to consider. The FAA's NexGen plan for ATM is predicated on using technology that will dispense with whirly round radar heads.

If I understand things correctly, ADS Broadcast and Contract will be a major navigation platform for which a "GPS" box is required. Squittering out will show your position to ATS and eventually being able to take in other squitters will let you see other participating traffic around you. Although this is aimed primarily at commercial operators (who don't like the equipage costs) the benefit will be there for anyone to take advantage of.

One important driver is the enhanced situational awareness the technology brings - something I would have thought AAIB would know and support.

SGC

Negative, or, at least, that is not what I read.

Guilty as charged.

Maybe they were meaning that it is becoming more common that the go to function is being used more when people are uncertain of position, then that track is not getting cross referenced back to the chart to ensure that your not going to go somewhere that your not meant to. And people arn't ensuring they actually know where they are mid waypoint thus their SA is compromised.

Or maybe folk have there heads in to much trying to work out what the box of tricks is doing when what it is saying doesn't agree with thier mental model of where they should be.

Just a suggestion.

There is a marked difference between a instrument trained pilot and waypoint usage and a VFR pilots use if they haven't been trained for it. There is also a big difference between an airways only Instrument pilot and a bandit country instrument pilot.

Well, at least in FAA-land you DO get trained for it when doing the PPL.

I wasn't aware that a GPS was manditory equipment in a FAA ppl training aircraft.

I am sure its the same in the UK that if its fitted the student is taught how to use it (never flown a school machine with it fitted to be honest). But in both cases I should imagine that the standard of training and best practises is in the hands of the instructor.

In both cases an old hand hairy arsed GA pilot will give quality instruction which will guard against fixation and duff in equals duff out. And a zero to hero cluless wonder will be the blind leading the blind.

In FAAland a student on their PPL checkride is expected to be able to competently use everything in the aeroplane.

If it has a GPS, you're supposed to be able to use and integrate it into your flying.

If it hasn't, you don't.

G

MJ, I wasn't clear. GPS is not mandated in an FAA training a/c, although if it's there the examiner can (and will) check if you can operate it correctly. I also assume, given the evolution of US airspace and ATC structures, that GPS usage is an integral part of training today.

What I as referring to was radio navigation (VOR, NDB) which is part of the FAA PPL syllabus and you are most definitely tested on the use thereof. Guess I misread your 'waypoints', but in the US you do learn how to navigate to intersections (which are waypoints of a sort) using VORs during your PPL.

Nav aids is also taught in the UK as well. Its part of the required ICAO syllabus.

And there are several ways you can use a gps which arn't just direct to a way point.

For example if you are operating close to a boundary and don't have an airspace warning capability you can make a waypoint up and run a track from it (persudo VORTAC) so that you can always keep to the one side of that track to remain clear of the airspace. Handy if you taking photo's near CAS.

You may be right Jan. I have no special expertise here, I just keep on reading it (e.g. links below). Also, I would hope that secure banking systems would not place too much reliance on internet-based timing information. But given the current problems with some UK banks' payment systems, I could believe that too!

From the Light squared debate (2012):
Coalition to Save Our GPS

From the New Scientist (2011):
GPS chaos: How a $30 box can jam your life - tech - 06 March 2011 - New Scientist

Mad Jock

I ferried a beat up old Citation which was indian Registered and changed to N reg from New Delhi to the UK.
It was an awful aircraft! You didnt need sim training with that bird as you got it for real :)
Thing was it had an old Kingt 90B GPS. With a very late departure from New Delhi and a very green co pilot with me we departed at night and in a monsoon for Karatchi in Pakistan then routing to Dubai across Saudi to Alexandra,Malta Marseille UK.
Last minute I asked if the GPS had a worldwide database which I was assured it had but it had not.
Halfway up Saudi NOTHING. We had to load every single waypoint enroute by hand from lat Long all good for the soul as well as landing into a sandstorm in the middle of Saudi at a military base.
No moving maps flashing screens and pretty colours just hard work.

Pace

Not so. I did my FAA PPL checkride in an LSA which had no radio navigation equipment.

That's true but it is getting very hard now to avoid modern avionics when doing the FAA PPL, because most schools have modernised, and the examiner will request a demonstration of competence on all installed equipment (to the extent compatible with the license privileges i.e. no need to demonstrate GPS approaches when doing the PPL :) ).

Whereas in the UK, any installed GPS is turned off during the skills test, and probably during all the training (at most schools, anyway, even though a GPS can be used in most of the PPL syllabus).

Anyway, the length of this thread shows how much negative impact a silly little one-liner in what purports to be an official organ of the CAA can have.

Frankly I'm baffled. A gadget which eliminates all uncertainty over where you are 'decreases your situational awareness'. And how does that work?

You know courtesy of the not invented here, work of the devil, GPS - and that knowledge decreases your situation awareness - because the others are stiull using ADFs? Or it is a Yankee conspiracy to reduce the skill set which real aviators need?

Even if someone is doing a classic 'Darwin Award' they are unlikely to turn right onto a railway line or turn left into a canal. Even the poorest GPS will likely have a line indicating controlled airspace.

Even if it doesn't they still do know where they are - which would not have been the situation previously (pre-GPS)..

A bit more thought would have been appropriate - particularly from a body like the AAIB. Or are they heading back into G-styx terriority?

Singing "this the road to ha'il" pace ;)

Long live the mighty trimble. And a slow painfull dose of D&V to those that jam GPS when there is sod all on the ground.

There is actually another possibilty which your not going to like.

That is that they have statistical data to back up that cockups with GPS are a major factor in loosing SA and busting airspace.

It all comes down to what the pilot says after they get thier collar felt post event.

Do these box's with airspace warnings take into account altitude when they give a warning?

If they jam GPS over a wide area, they will have a lot of fun with all the aircraft which

- are flying IFR
- are flying in CAS
- are required to be BRNAV compliant
- have an IFR GPS as the only possible/practical means of BRNAV compliance
- have been given a nice 200nm DCT by ATC :)

That includes everything meeting the above scenario, right up to big business jets. Very very few bizjets have INS or IRS; GPS-based RNAV FMS is the standard fit.

According to a Eurocontrol nav conference I went to a while ago, the planned fallback for loss of GPS is ATC (radar) vectoring, which is fair enough but the ATC workload will go way up if they jam GPS over a wide area and they do it from a reasonable altitude so that airborne aircraft (with proper roof-mounted GPS aerials) are affected too.

I suggest you don't fly in Scotland then Peter. Last year it came up in parlament that the fishermen were knackard and could the mil please turn it off.

And most planes FMS has DME/DME as the primary and VOR/DME or VOR/VOR as the fall back for position fixing. So I doud't even 1% of the big stuff would even notice that the GPS was out. They would just press the msg button twice to stop it flashing.

And the area that I was commenting on you don't get 200nm directs you get 500Nm directs with no VHF coverage and just miles and miles of sand with the occasional rocky out crop and some polo shaped fields of green.

Meldex they have a standing instruction that anywhere in the UK there maybe GPS jamming without warning.

I suspect that the first sign that something is kicking off will be the GPS going off line.

I doudt very much they will have time to put a NOTAM out. And it will have zero effect on commercial flights in the area. If they turned off all the DME and VOR's as well it would be chaos.

Meldex, I'm sorry but if you looked at the notam I posted it had a much more significant area than just Sailsbury. I was surprised for a pilot to ask the question you did, especially one who is used to reading a notam? It extended 65nm surface to FL400. Good fun for any airliner enroute to Birmingham from the south on the day, but no one complained, no airliners came crashing down.

As you will be aware notams can be issued on the day. Also in the event of an "incident" at the Olympics we may not get any notice...

One that I fly (G1000) is pretty well always saying "warning airspace within ten minutes". Guess whether I take any notice of these warnings.

Maybe this "feature" is designed for the American mid west, not the south east of England.

Also unhelpful is when it says "within airspace" when you're not inside anything that matters, or that you're interested in, or that you can find on the map.

Thanks Wombat.

The airspace warning is turned off on all the work machines for obvious reasons.

I did suspect down south it would be going off all the time. My thoughts were that alot of these busts were underneith steps in airspace and if the box of tricks took into account vertical as well as horizontal position. Sounds like it doesn't if its saying you are in it when you have an airway overhead below 10k

Even the £159 Aware gps has "Visual Airspace warning, intelligent to your current height".

What annoyed me about the article that after having mentioned these causes of accidents/incidents it did not substantiate or even attempt to explain/give examples of this "over-use" of GPS...

If the guy who wrote it had actually given an explanation for the assertion we might actually have been able to comment on it. I appreciate the CAA sending out a magazine from time to time but many of the articles in it (including this one) had absolutely no substance to them or said anything of worth.