My GNS430W is lost!

[ForkTailedDrKiller]

I have 500+ hrs with the G430/530 flying all over Australia and I have never before seen anything like this.

I would be interested to know if anyone else has had a similar experience to the following:

Yesterday my G430W went bush going into Tindal! I had a YBMA-TEXAN-BARON-YPTN flightplan active. The final waypoint was YPTN, which I assume is the aerodrome reference point, rather than TN (for the NDB or VOR) because this is the correct way to do it with a G430/530 - it lets you then call up arrivals and approaches for that aerodrome.

About 30 nm out from Tindal, it became apparent that something was amiss. I could see where the aerodrome was, and the Garmin 496 portable on the yoke was indicating what would have been the correct track to the aerodrome, but the GNS430W, which was connected to the autopilot at the time, was headed for somewhere well east of the actual Tindal aerodrome. The point on the 430 map display that was marked as YPTN was not where the aerodrome was actually located.

In hindsight it would have been interesting to set it up for an RNAV Appr and see what happened, but I didnt think of that until after I had landed.

Can anyone suggest something I might have missed?
Does anyone know where you report apparent GPS anomalies?

I will probably go back through Tindal on Friday and will fly an RNAV appr (in VMC).

Dr :8

PS: My faith in GPS technology has taken a bit of a beating!

[Jabawocky]

Could it be a Jepp error? Check the data in the 430W against your Jepp charts. You may find the bug!

Interesting thing is who do you report it too.......well ATSB? Jeppersen? Where will it get taken seriously. If you flew the RNAV and wound up aiming at some blokes back paddock then you would have had an Incident to report!

I have also found the CTA steps on the G296 are not the same as a VTC around Brisbane. Which may explain why some folk get VCA's and why ATC get a lot of stress in their day!:ooh:

Watch out for the PP up there to! :ooh:

[Kickatinalong]

Might be set up with the old strip co-ords?
Kickatinalong:confused:

[Horatio Leafblower]

GAO FIRES WARNING ON GPS
"It is uncertain whether the Air Force will be able to acquire new satellites in time to maintain current GPS service without interruption," warns the GAO. "If not, some military operations and some civilian users could be adversely affected." The report, issued April 30, notes the Air Force's struggle to successfully build satellites on time and on budget. According to the GAO, the Air Force is running $870 million over its original cost estimate and has delayed the launch of its next satellite (now scheduled for November 2009) by almost three years. As old satellites begin to fail, it is increasingly important that the Air Force does not fall behind its current schedule. Otherwise, warns the GAO, there is increased likelihood that by 2010, "the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to." That shortfall "could have wide-ranging impacts on all GPS users." While many of the potential problems rely on the Air Force's success working with a new contractor, the GAO has made recommendations. More...



Better put all those VORs and NDBs back... :=

[Tmbstory]

Remember it is an aid to navigation, it pays to keep a healthy respect to any situation and if possibile, have a second alternative navigation aid ,also set- up.

Tmb

[Stationair8]

FTDK you were approaching the NT's Area 51 and black fella sacred site.

[sms777]

I think your 430W got a bit jealous because you payed too much attention to your 496. Just wait till the rest of your GPS's go on strike..... you will never find your way back home to annoy Jabba again.....
:E

[muffman]

This is probably unlikely given it's your own unit but I once flew a rented aeroplane and somebody had inserted a user waypoint of WOL, which is also the navaid identifier at Wollongong. During data entry I should have noticed that it said USER instead of NDB next to what I had selected, but instead only noticed it when the track/distance was a long way off.

[27/09]

I'll bet it has SBAS or WAAS enabled.

When you are outside of SBAS coverage you need to disable SBAS or WAAS.

Go to AUX page 4 which I think is headed Setup 2 and you will find a label called "SBAS Selection". Highlight that selection and press enter. You should see WAAS and my bet is that it is ON. You need to turn it off.

In this part of the world we can receive the signals from the WAAS satellites but the correction factors are not for this part of the world and can cause significant errors for WAAS enabled GPS's.

I'd be interested to hear back from you after you check this out.

[ForkTailedDrKiller]

I'll bet it has SBAS or WAAS enabled

Good thought but, nope!

Dr :8

PS: But I will go check tomorrow in case someone has had a play with it - unlikely as I am the only person who flies the aeroplane.

[bentleg]

To pinch a post from another forum "You used a Garmin" :=

[27/09]

Have a look at the EPU (estimated position uncertainty) values on Nav page 6 and the HFOM and VFOM for that matter if this happens again.

I know that there have been some isues with the 430/530W units having very high EPU values. I thought is was all to do with the SBAS issue but there may be more to it.

[porch monkey]

And there is the lesson for those types who operate via D To ENTER!!, and hope/wish/pray/don't give a ****.

I don't mean you Dr, You've just demonstrated what can happen, even if you know what you're doing. Think about those that don't!

[VH-XXX]

I've had the exact same thing happen on the GNS430 in the Cirrus coupled to the autopilot and avidyne. I was heading towards the CBD with it clearly in site some 40 miles away, looked down for a while whilst reading the paper, looked up and I was headed for the mulbury. I did a re-goto and it put me back on track. I was kicking myself at the time that I didn't take enough notice of where it was actually trying to take me. This occurred around the time of the Benalla crash when I posted here and ATSB spoke to me at the time regarding GPS issues.

Not long after (couple of months) same thing happened on 296. Headed for Wangaratta, could clearly see the field no more than 10 miles ahead but the ETA was some 25 minutes which made no sense at all (unless I was in a Thruster which I surely wasn't). Yet again was kicking myself that I didn't look closely as to where it was actually trying to take me.

Both of these were some 2-3 years ago.

[Jabawocky]

could clearly see the field no more than 10 miles ahead but the ETA was some 25 minutes

Have seen this on an old G295.......... and a mobile phone was involved :hmm:

As much as we often get away with things with phones, there are times when I wonder..... have seen it kill a transponders Mode C.... probably due to the encoder to transponder harness..... but it did.

This is possibly a database error, but I am sure the Dr will keep us informed, he has to get back to TL via there anyway!

J

[Deaf]

I have also found the CTA steps on the G296 are not the same as a VTC around Brisbane. Which may explain why some folk get VCA's and why ATC get a lot of stress in their day!

There can be issues with the 296 software and steps. I am always getting warnings approaching/in CTA when clear of CTA to the north of Melbourne (based at Sunbury). The steps on the 296 are as per the VTC, just the warnings are the problem. One explanation I have heard is the 2000' extension for 16 causes problems for the algorithm even though the problem also occurs 2 steps away.

[VH-XXX]

I keep my 296 pretty much up to date and haven't had a problem with the steps. It does give a lot of warnings but they are fairly generic and if you're fast will pop up fairly early. eg,. airspace ahead within 10 minutes, which could be 20+ miles depending on your speed. If they are causing you problems you can of course filter them out so they don't appear.

[Jabawocky]

Steps and the warnings are fine, they have a distance and height buffer I think, its the actual steps on the map compared to the VTC that is wrong.

Back to the FTDK GNS430W issue......

[ForkTailedDrKiller]

he has to get back to TL

....and how am I gonna do that now that my faith in GPS is totally destroyed?

Dr :8

[slackie]

....and how am I gonna do that now that my faith in GPS is totally destroyed?

Hey, remember VORs, DMEs, NDB/ADFs, map reading and dead reckoning??

[Pinky the pilot]

Better put all those VORs and NDBs back...

Wot Horatio said!:}

Never mind Forky, You'll get over it!:ok::D
At least you've proved that having more than one unit can be of use.

[ForkTailedDrKiller]

The co-ordinates for YPTN in the G496 and the G430 are as follows:
G496 - 14 31.27; 132 22.66
G430 - 14 31.27; 132 22.67

The snail trail on the 496 clearly shows the aeroplane tracking a straight line that would have missed Tindal by about 5 nm - until I intervened!

Dr :8

[sms777]

Ever thought of blaming that worn out military satellite instead of your trusty receiver :hmm:

[Jabawocky]

Can you lodge some kind of incident report with someone who will do something?

CASA would be the first choice..... you have mates there! :ok:

[RadioSaigon]

G496 - 14 31.27; 132 22.66
G430 - 14 31.27; 132 22.67

Only a handful of metres there... just doesn't make sense..

Has the 430 had a firmware update or anything like that recently?

[Joker 10]

Good thing it wasn't outputting to ADSB could have been a disaster !!!!!

Or maybe just shows the fallability in relying on GPS for accurate position rather than SSR in busy terminal areas.

[ForkTailedDrKiller]

RS - I had the WAAS upgrade done about 12 mths/200 hrs ago. Never had any problems with it before.

Dr :8

[OZBUSDRIVER]

Crikey, yes it could well be a problem there Joker. If it was satellite based then everyone in the immediate area would all be skewed the same distance. It it was unit based then.....more investigation is needed.

XXX your thoughts crossed my mind back around the time of the BLA crash.

What it does indicate is the need for WAAS ground receivers to augment if there is a dud satellite. Which brings up the next question...why didn't FDE kick in and block the dud signal, Doc?

[Barkly1992]

I was once (in the 1980s) in the right hand seat of a CAA V-tail (B35) flying Canberra to Coffs Harbour on an IFR plan.

The PIC said to me somewhere about Port Macquarie - "what are you doing?" as I looked out of the right hand window with a WAC chart in lap; a prayer wheel and my brand new Avstar calculator, scribbling on a pad.

I replied "navigating".

His reply was "the department wouldn't have given us all of this navigation equipment (VOR; DME; NDB etc) if they wanted you to look out of the window.

As we were in VMC - explains why there are some near misses.

Barkly

[bushy]

I din't know that CAA had vtails. I thought they were all B36's, even though they only had four seats fitted.

[Jabawocky]

They had a few, I have seen pics on pprune here of them!

[Peter Fanelli]

I din't know that CAA had vtails. I thought they were all B36's, even though they only had four seats fitted.


Clearly you are not old enough to know.....:E

[Chimbu chuckles]

Definately had V35s...my first Instructor and the Chap who gave me my initial CIR were killed in the CAA V35/Glider midair at Tocumwall...knocked off one/both of the ruddervators and then spun in.

Re the GPS error...one is working fine and the other not indicates it isn't in the satellite clock but rather in the G430W unit itself. Software glitch?

Was it a consistent 5nm all day or just nearing YPTN?

[404 Titan]

ForkTailedDrKiller

I remember you only recently showing photos of your GPS loosing its position. It may be the aerial or it may be that the GPS needs to be reset, i.e. letting it look for the satellite constellation again just as you had to when you first bought it. I haven’t used a GA GPS for nearly ten years but most have a means of doing this. Refer to its manual or if this fails an avionics tech.:ok:

[Flopt]

Yeh ,my testing officer arrived in one in Bundy 'bout 1983 for my PPL test.
Endearing chappie named Charlie Moggs as I recall......claimed only "divine intervention" allowed me reach the runway at YGAY when he 'failed ' the donk...
Knew there was something about them that put me off.....

Getting back to the topic my G155xl has an occasional tendency to head left as it passes inside 30nm from destination...if it's coupled and I am self briefing for an approach for a few seconds it seems to wander a fair bit...but corrects if I hit the 'direct to' button....had my antenna checked as on a rare solo in 'the' FTDK going into YBTL the pre- WAAS 430 took me off track , ...and was only transmitting on Com2...and turned out to be a loose connection? or not plugged into the rack fully? or something like that?

Have ya had that checked Doc?.....she shakes and rattles a bit...

Flopt

[Peter Fanelli]

From Fox News

"Mismanagement and underinvestment by the U.S. Air Force could possibly lead to the failure and blackout of the Global Positioning System (GPS), a federal watchdog agency says. The risk of failure starts in 2010, according to the Government Accountability Office (GAO) report quoted by PC World.
The failure would impact not only military operations, but also the millions of people and businesses who rely on the satellite-based navigation systems built into cars, boats and cell phones.
"If the Air Force does not meet its schedule goals for development of GPS IIIA satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to," the GAO report states.
The report says the Air Force has struggled to build successful GPS satellites within cost and on schedule."




GPS System Could Begin To Fail Within a Year - Business Center - PC World (http://www.pcworld.com/businesscenter/article/165126/gps_system_could_begin_to_fail_within_a_year.html)

[Jabawocky]

A few things for any Avionics techs to answer?

Mobile phones..... coming into range of ground stations and pinging out hard!

Old RG58 Coax.... and maybe not really good connections.

Maybe upgrade to RG400 Coax and all new crimped connectors.

Keep all GSM/Next G devices turned off and see if problem repeats itself. Then Try again and a again with them on. If in IMC make sure all are off.

I have seen G295(5 yrs ago) with own antennae connected (no coax) do a similar thing and also about the range for GSM starting to reconnect. :hmm:

J:ok:

[Old Akro]

FTDK, was the antennae replaced with the upgrade? As anntennae age they pick up fewer satellites which can lead to innacuracies. I guess its ditto for the wiring & connectors, but I think less likely.

If the 496 was OK, then I think it rules out a RAIM black hole or electromagnetic interference. You've ruled out a database problem, which leads to a reception or processing problem.

The GPS is actually a less complex device then we imagine. It recieves a data string from a satellite, does a bunch of math, then displays the result. All the smart bits are in the math. The reciever part is simple.

[RadioSaigon]

Given the fact that the 496 behaved itself during this sequence of events -as it did in the previous event when the 430 went to DR mode, I would be deeply suspicious of a software (firmware or possibly something in a recent database update) bug or electrical fault in the unit itself. As others have suggested, I'd be inclined to do a full system-reboot as far as is possible initially, as well as check the WAAS/SBAS systems are entirely disabled. If that didn't help, then it'd be off the the Dr's Shop (GPS Dr rather than the FT Dr :eek:) to have the unit thoroughly assessed and the antenna's connections checked. Do Garmin have any sort of user-feedback system you can check? Surely there must be somewhere end-users discuss issues with their units? Jeppesen don't have anything I can see (I've looked) which seems strange... their databases are not always the be-all end-all, particularly for the VFR units.

Jaba: interesting comments re the coax... can you add any more info on the shortcoming/benefits of the various grades?

Another thought occurs... I know you'll have considered this, but I'll ask anyway: is there any possibility the 430 had dropped into approach-mode and was guiding you to an RNAV fix for an approach? Stupid q I know...

Did you have any opportunity during the sequence of events to see where its current goto was?

I'm really interested to see what the outcome of this will be!

[Jabawocky]

I am not a guru on the coax thing, however the RG400 is the ducks nuts now apparently, is double shielded and nicer looking centre conductor.

Other interesting thing, your GPS antenna coax must be around 17 feet or more long. That is a big deal for impedance apparently.

Main issue I have seen is a G295 showing wrong data and pointer due a mobile phone.

RS has some things to check.... the app mode??

I too am keen to learn.

[27/09]

I remember reading/hearing somewhere that some receivers need new coax and or aerials though I cannot remember if this was for an older GPS being replaced by a newer one or for the upgrade to W status for the 430. I'm pretty sure it was for the W upgrade.

I know the at least from a legal perspective that the 430 and 430W are not plug and play and I think there are physical issues as well as legal ones. Either way I think using old coax and aerials would cause a Loss of Integrity problem (which would be flagged on the GPS) this is not the issue that the Doc had.

What it does indicate is the need for WAAS ground receivers to augment if there is a dud satellite.I agree we need WAAS in this part of the world but WAAS is not designed to augment dud satellites.

Which brings up the next question...why didn't FDE kick in and block the dud signal, Doc? How would you know when the GPS is using FDE to disregard a bad signal, unless there were insufficient satellites left to obtain a position solution then you would be getting an integrity warning.

Keep all GSM/Next G devices turned off and see if problem repeats itself. Then Try again and a again with them on. If in IMC make sure all are off.

I have seen G295(5 yrs ago) with own antennae connected (no coax) do a similar thing and also about the range for GSM starting to reconnect.

Good idea to keep cell phones switched off. There again in my opinion they would cause a loss of integrity or RAIM warning.

Handhelds don't have RAIM or FDE capability so would not give any warning even though they may be giving dud navigation information.

From what the Doc says there were no warning messages from the GPS.

These units meet the standard for sole means navigation, which means that they meet certain standards to guarantee accurate navigation providing FDE calculations are done for the route and the time of the flight. They also give warnings when navigation is compromised.

I still stick by my original theory about WAAS being enabled.

I guess it is possible that something was going on at Tindal and the US Department of Defence had reason to downgrade coverage in that area however I don't think that would even explain the error the Doc mentioned.

[Flying Binghi]

...I guess it is possible that something was going on at Tindal and the US Department of Defence had reason to downgrade coverage in that area however I don't think that would even explain the error the Doc mentioned.

Maybe FTDK gave a hint of what the problem was on that flight.

FTDK mentions this in another thread "...they were caused by a UFO passing through at warp speed!.."




........:}

[RadioSaigon]

... something was going on at Tindal and the US Department of Defence had reason to downgrade coverage in that area...

hmmm... doubtful, methinks. That would lead to the 496 giving erroneous guidance also, surely? And wouldn't such an event be NOTAMed?

[ForkTailedDrKiller]

I remember reading/hearing somewhere that some receivers need new coax and or aerials though I cannot remember if this was for an older GPS being replaced by a newer one or for the upgrade to W status for the 430. I'm pretty sure it was for the W upgrade.

The coax and antenna were replaced for the WAAS upgrade.

Dr :8

[27/09]

hmmm... doubtful, methinks. That would lead to the 496 giving erroneous guidance also, surely? And wouldn't such an event be NOTAMed?

Good point though I'd doubt it would necessarily be notamed in all cases.

[PlankBlender]

Dr did you check RAIM via the ASA site on that day? There are almost daily short outages for FDE (I think due to satellites going outside useful sight so to say), and that might have impaired the FDE which could contribute to the error. I don't know how the W software works and whether impaired FDE could actually be worse than normal RAIM processing, but from a software perspective I'm with the other sceptics here and would say give the unit a firmware check and a few test flights --finally a chance to use the plethora of backup GPS's ;)

Have a look at this RAIM prediction for today for Tindal, I get similar results around BN pretty much every day..


TINDAL (YPTN)
GPS RAIM PREDICTION 191400
YPTN
TSO-C129 (AND EQUIVALENT)
FAULT DETECTION
NO GPS RAIM FD OUTAGES FOR NPA
TSO-C146A (AND EQUIVALENT)
FAULT DETECTION
NO GPS RAIM FD OUTAGES FOR NPA
FAULT DETECTION AND EXCLUSION
05192021 TIL 05192035
05200815 TIL 05200837
05202017 TIL 05202031
05210810 TIL 05210833
05212013 TIL 05212027
05220806 TIL 05220829
GPS RAIM FDE UNAVBL FOR NPA

[geeup]

PlankBlender
Can you forward me the link to that website with the GPS outages.
Does it only cover Australia?
Cheers

[27/09]

Plankbender

It is my understanding that you will get an Integrity or loss of RAIM warning during those periods. Since there was no warnings I don't think it is an FDE or RAIM issue.

[ForkTailedDrKiller]

Mystery solved!

You can all go back to faithfully following your GPSs.

The world has been restored to its normal axis!

Fantastic gear - idiot pilot!

Dr :8

[RadioSaigon]

Fantastic gear but ******** pilot!
Oh Come ON!!! Put us out of our misery!!! Wot happened?

[ForkTailedDrKiller]

Oh Come ON!!! Put us out of our misery!!! Wot happened?

Not saying - and you can't make me!

Dr :8

[RadioSaigon]

Not saying - and you can't make me!

ROFPML! :p

Can probably guess what might have gone on then... can happen to any of us. Pleased it's all ducks-in-a-row again! :ok:

[PlankBlender]

geeup, where are you located? Hagen/Germany? For AUS and nearby territories, it's here: Airservices Australia - Flight Briefing - Pilot Briefing Services (http://www.airservicesaustralia.com/brief/aismet.asp)

You should have the equivalent in your country, here's a tool from Europe that seems to work globally: AUGUR GPS RAIM Prediction Tool - Terminal/Approach Tool (http://augur.ecacnav.com/augur/app/npa)

AUGUR also shows up the small outages I alluded to in my earlier post (enter YBAF for example).

DR c'mon, spills the beans, we could all learn something!

[ForkTailedDrKiller]

RS

Psssst! If you promise not to tell anyone - I had a parallel track offset selected.

"When you reach the end of the flight plan, a message will state 'parallel offset track terminating in X seconds'. The message will be given when the aircraft reaches the offset distance from the end of the parallel track. This will give the pilot sufficient time to intercept the original course."

Had I been in IMC (and therefore not been able to see where the aerodrome was from 30+ miles out) I would have got the message and hit the "direct to" button!

I have made a considerable effort to learn the ins and outs of G430W (as you must with GPS), but I had forgotten that one!

Thanks to all who suggested what the problem might have been.

Dr :8

[RadioSaigon]

ooh yeah, that's a 'gotcha'! But as you say, it would have taken you where you needed be! Thanks for that -something we all need to be aware of.

[sprocket check]

- I had a parallel track offset selected.

Why would you do that?

sc

[RadioSaigon]

Why would you do that?

One place I flew, we used to offset one dot to the R religiously every flight in and out-bound... simply to prevent the deathly accuracy of these things bringing 2 company aircraft on reciprocal tracks at around the same level together. Obviously not necessary to go into all the ins & outs of the why's & where-for's here, suffice to say, had the (VFR) GPS's we were using had the ability to provide a programmed offset, we probably would have used it.

[Agent86]

The Offset (or parallel track) feature can cause all sorts of problems at the end of the flt. This is mainly caused by the very small sector from the Navaid to the Airfield (ie TN to YPTN). I have seen up to 30 miles and 5 minutes "added" to the total dist/time due to the system trying to work out how to add the xx mile offset to a half mile leg distance. Once you load the runway/Star/Approach, this small sector is removed but you can still have problems.

[27/09]

Pleased you got it sorted and your faith in technology restored. The parallel track option wasn't something I had thought about, it's not something I would be likely to use.

Even though you probably feel rather sheepish about it all, it was very noble of you to share what caused the problem. Your frank admission might save someones bacon one day.

[VH-XXX]

Isn't it an actual requirement to track 1 mile to the right of intended track to avoid conflicting traffic in the opposite direction? (even moreso with the advent of GPS)

[Jabawocky]

not required, but desirable!

I never followed the direct track.....but thats another issue! :}

[slackie]

If I was trucking around IFR then I'd definitely be doing it. Standard Lateral Offset Procedures (SLOP) ensure that if there is a cockup (whether ATC or Pilot or both) and 2 aircraft are on reciprocal tracks at the same altitude then they won't touch nosecones. It's amazing (and I'm probably preaching to the converted here!) how accurately a coupled autopilot (and some pilots for that matter) can track. I remember being in the upfront in an ATR out of NZQN for NZCH when the TCAS displayed opposite direction traffic 1000ft below in our 12 o'clock at xx miles. The aircraft (another ATR) passed directly below us and had we been at the same level then each pilot would've been introducedintimately with the other co-pilot!!:eek::eek:

As a VFR only pilot I tend not to fly directly between points but meander a little (mostly 'cos I can't fly straight anyway!), and about 80 - 100ft below the VFR cruising level (again mostly 'cos I can't fly level!) just so I have a better chance of seeing most of the other VFR aircraft. My aircraft has particularly poor visibility (especially if someone is sitting in the front cockpit). There are some places that I won't fly (like near NZHN around Templeview or Cambridge at 1700ft) 'cos I know that every other man and his dog are likely to be there too!! And once I'm given a standard Arrival Procedure (and traffic information) I'll climb/descend to 1700ft a little wiser and probably much safer!!

[27/09]

If I was trucking around IFR then I'd definitely be doing it.I would sincerely hope you were not doing that. As far as I know it's not an approved procedure for IFR flight. I'm sure that the boy or girl pushing tin in that airspace would't be impressed either.

Quite OK for VFR, but IFR??????????????????????

There are some places that I won't fly (like near NZHN around Templeview or Cambridge at 1700ft) 'cos I know that every other man and his dog are likely to be there too!! A system designed by ATC to ensure any air to airs happen outside of controlled airspace. :E

[Peter Fanelli]

If I was trucking around IFR then I'd definitely be doing it. Standard Lateral Offset Procedures (SLOP) ensure that if there is a cockup (whether ATC or Pilot or both) and 2 aircraft are on reciprocal tracks at the same altitude then they won't touch nosecones.


Unless the cockup is that one of the pilots has selected the offset on the wrong side.

[OverheadPanel]

Well the old ageing 767 I was on the other day with a 2nm R offset put it bang on the opposite direction traffics track. (I think it was a 777 so it would have had GPS). Our fine nearly 20 yr old machine didnt have such a luxury item as a GPS.

We would be better off with its random IRS errors to not put us anywhere near the correct track anyway.

[slackie]

27/09
SLOP is a recognised procedure...all tracks that are separated laterally have contingency built in to cope with navigation "error"...SLOP fits in with this "error"...I'm certainly not advocating large offsets.

A system designed by ATC to ensure any air to airs happen outside of controlled airspace.
The HN procedures were designed, tested, developed with input from the local users (that could be bothered!), and I get sick of hearing those who want their cake and eat it too...."I want to operate in controlled airspace, but I don't want to have to comply with any instructions, but if I come close to another aircraft then it's ATC's fault"...please give it a rest!!:ugh: Airmanship just doesn't seem to part of the training syllabus anymore (at some places). Common sense should dictate that in uncontrolled airspace you'd avoid areas of potential conflict. Or am I wrong.

In the interests of avoiding hijacking this thread I'll avoid commenting more here...but if 27/09 wants to start another thread then I'd happily elaborate.

[ForkTailedDrKiller]

So I guess the only question left unanswered is why would the Mad Dr dial in a 5 nm parallel offset track?

Good question!

If I am on an IFR plan I generally dial up a 1 nm right parallel offset track - but I was VFR!

I realised that my track was going to take me almost right over the top of the No.3 Outstation on Rocklands north of Camoweal! So I dialled in the 5 nm offset so that I would pass just to the east and be able to take a pic. I spent many hard days and quite a few hard nights there, back when I were a young fella!

This will bring a nostalgic tear to the eyes of any ex-Stanbroke pilots out there.


http://www.fototime.com/E85E8053B0579EE/standard.jpg

....and a couple from 35 yrs ago!

http://www.fototime.com/B4A5083869F1B43/standard.jpg

http://www.fototime.com/7A9D2BA33FB6C8D/standard.jpg

What a top spot!

NOT!

Dr :8

[27/09]

Slackie

I fly IFR quite often. I've never heard of SLOP. Where is it in common use? Where does one find out more about it?

[Jabawocky]

If I am on an IFR plan I generally dial up a 1 nm right parallel offset track - but I was VFR!


VFR Forkie!!!! :eek::uhoh::eek:
Forkair SOP's specifically state no VFR flight above 1500'AGL and further than 5NM from the departure aerodrome

The CP will want a chat with you when he see's the height that pic was taken from! :eek:

Yeah I know our backward ATC in the outback has no VHF.......you will need to ammend the SOP's.

[slackie]

STRATEGIC Lateral Offset Procedure (SLOP) is normally used in high level cuise by turboprop/turbojet aircraft, and is common in Oceanic airspace, in fact I think it was widely introduced in Oakland/Anchorage Pacific airspace back in late '04/'05 for those aircraft suitable equipped. I am sure that aircraft DON'T need to request it but when in radar contact must maintain their offset (usually 1nm right of track) so the controller can anticipate their track will remain constant (offset).

Google it...there's probably lots around...

In fact have just done it and here is Wikipedia entry.... Strategic Lateral Offset Procedure - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Strategic_Lateral_Offset_Procedure)

[geeup]

Thanks PlankBlender
I'm currently in Mt Hagen PNG :8
Airservice may cover us :ooh:

[harrowing]

Another trap is going into YBTR (Blackwater). The lat/long for the enroute waypoint and the aerodrome are the same, however the FMS (flight management system with integrated GPS) units we use on the DHC8 will allow an RNAV to either, with most of the tracks and distances agreeing except for the last and most critical leg, hence the requirement to check each leg before doing the approach.
Generally the first option that comes up if diverting to YBTR is the waypoint and even a lat/long check will not pick up any problem.
It is quite amusing to see the look of disbelief in a new F/O when the two approaches can be compared on adjacent systems.
Always have a healthy respect for automation and GIGO.

[sprocket check]

OK, here is big brother's statement re SLOP:

http://www.airservicesaustralia.com.au/flying/specopinfo/docs/gps.pdf

sc

[Brian Abraham]

With all this talk about SLOP, why not go back to astro? Ought to fix separation problems. :E

[27/09]

SLOP

Even though it was advocated for IFR use by Slackie it would seem that its not approved for that purpose in OZ and I am not aware that it's approved here in NZ either.

VFR only then it would seem, BUT don't forget that you have parallel offset enabled otherwise confusion may reign eh DOC. :)