The end of ADF at last?

[Gipsy Queen]

Is some of this resistance to the loss of ADF just nostalgia?

I have flown aircraft which were DF equipped - the "A" had not arrived then - and the advent of the automatic bit was just the most wonderful thing! I have no experience of ADF coupled with DME but we managed very well without the DME since nearly all aircraft had two ADFs on the panel and a circular computer in the flight bag. The system worked well although it did have its limitations. But nothing like as user-friendly as VOR/DME for example but we didn't know that at the time as we struggled to ascertain frequencies, obtain DF cuts and juggle the computer, pencil and paper, maintain the scan and verify a position in turbulent IMC.

This level of flight deck workload is stupidly high if there is an acceptable alternative -and there is. In fact, these days there are several choices so despite my sentimental attachment to the venerable NDB and its associated navigation, I can see no useful purpose in retaining it. Now if it's Console we are talking about . . .

GQ.

[Dan Winterland]

With night error, coastal refraction, turn error and the tendancy to point at the nearest thunderstorm, it's amazing that the NDB is still in existance. It appeared in the 1920s - imagine introducing and trying to get it certified now!It may be of some comfort to the GA flyer, but most GPS sets will give bearing and distance to a waypoint - so why not use that!

In the USA, nearly all NDBs have gone - I can't think of any off hand. Where I fly now (China), there are quite a few still around. This is historic and they are gradually disappearing. However, when we use them as a navaid, we will always have GPS as our primary navaid, so we are just referring to the position and not the NDB itself. And if we have to fly an NDB approach, it is essentially a GPS approach.

As part of the IR I used to fly on a Classic 747 (only two years ago), we had to fly an NDB approach. If faced with that situaion for real with weather on minimums, I don't think many of us would have not first considered flying to the alternate. In fact, our chief pilot hinted that he didn't want anyone doing it for real.

Consol - now there's a system!

[Semaphore Sam]

Come on guys. Times, and technology change. When I first started flying, they had Adcock Range approaches (N/A), Loran C (and probably B), Consolan, navigators, star charts, sextants, and Ocean Stations. The ADF/NDB had its day...the only reason to keep them (mentioned only once in an earlier post) is to get the news and broadcasts of sports events. These are admittedly very important..if technology can provide these services without ADF/NDB, they should go the same as steam engines and semaphores (sad, but part of life). Sam

[Fuji Abound]

Is some of this resistance to the loss of ADF just nostalgia?

I think this is the correct question - in other words do we need the ADF.

Practically, so far as GA and en route navigation is concerned the answer has to be no, because GPS has replaced the ADF even if VORs are being used with GPS filling in the gaps between low level reception.

However legally, and particulaly in so far as let downs are concerned, the situation is more complex.

There are a few places with only NDB/DBE let downs. They are the least expensive let down aids available to an airport authority. Such airports are unlikely to ever be able to afford a localiser or have a VOR positioned on thier field.

I hear you say what about GPS approaches?

GPS approaches suffer from a significant limitation. They require an approved panel mount unit. Now we all know most people will "supplement" such an approach with a GPS (hand held or otherwise). However, strictly if the ADF is removed from the aircraft then these approaches will become illegal for most GA unless they invest in an approved panel mount unit.

The use of hand held GPS units for en route or approaches in not likely to be approved any time soon!

[S-Works]

Please don't demean others by assuming we all want progress in private flying.

And please don't demean private flying by holding it in the dark ages. If you want to be stuck in the dark ages sucking oil and experiencing the nostalgia of a bye gone age then it is your call.

However the reason we have dwindling pilot numbers, so few IR's etc is the modern nintendo generation have no sense of nostalga and all they see is old !!!!can aircraft with equipment that should have been sent to the skip decades ago.

I use my aircraft as a practical tool for getting me around Europe for business and leisure and flying over 400hrs a year I get to do a lot of instrument approaches.

The ADF IS OK as situational awareness tool, but I also have much better tools in my cockpit for the job and will not lament it's loss other than for listening to Virgin 1215, but even that has been replaced with my iPod....

[Droopystop]

I never said I wanted to hold GA in the dark ages. I happen to agree that some new airframes would do the flying schools a whole heap of good. I was merely trying to point out that not everyone in private aviation want their own private airline. Nor does every IR holder dispise ADFs.

[Itswindyout]

think outside the BOX

there are many countries that use adf/ndb facilities, that a UK PPL might visit.

Also they are a godsend, as situational awareness for ILS approaches.

I have just demonstrated the two NDB approach in Russia to a non believer.

He is also an american, who would not know an NDB if he fell over it.

Yes I know, I have a very high tech cockpit, but still when the chips are down like to think that I could conduct an approach with the little needley thingy.

In a former life I was able to navigate day and night over the UK, using the BBC transmitter location guide, also not forgetting Droitwich, centre of the known universe.

Please do not loose your basic skills.

its windy out

[bookworm]

Also they are a godsend, as situational awareness for ILS approaches.

You're winding us up windy... ADF for SA? Have you flown with a moving map?

[Fuji Abound]

In a former life I was able to navigate day and night over the UK, using the BBC transmitter location guide, also not forgetting Droitwich, centre of the known universe.

Low level using the football and other stadium lights works well also. Never understood why the lights arent marked on maps. You have just got to check that you coinicide your flight for when they are switched or otherwise they fade, a bit like the ADF needle.

[IO540]

Statements like

In a former life I was able to navigate day and night over the UK, using the BBC transmitter location guide

make me wonder how many trolls are in here.

Before the invention of controlled airspace, maybe. What's that, about 1950??

[Sir George Cayley]

I think the proposal from CAA is to remove the requirement, not to remove the equipment.

Therefore, should providers continue to support transmission, users who retain the onboard equipment can use it.

Far as I can see there is no move to take the NDB approach out of IMC training and testing as a result of GPS introduction.

And, it's only in UK airspace. No sign of Europe following suit.

So, lots exchanges about not a lot really.

Unless you won £35m this weekend and are about to order a Columbia 400!


Sir George Cayley

[bookworm]

So, lots exchanges about not a lot really.

Not unless you're currently paying thousands of pounds for the privilege of completely ignoring the ADF while flying IFR in controlled airspace, no.

[mm_flynn]

If ADF and DME could be replaced by GPS (as in USA). I would tomorrow junk my KNS-80 (for its DME) KN-53 and KR-87 for a 430 to match to my 530.

[Itswindyout]

various responses

I actually used Avonmouth docks, and the turning point, nice glow from the flare stacks at the chemical works.

The BBC Driotwich transmitter was my prime nav aid from Manchester to Bristol, at 3000 ft, and as it was turned off for a few hours every early morning, to be establised on track backtowards Brisol was critical, until the flare stacks ( or glow) were visible. NO motorway to follow like todays IFR pilots.

I currently fly the G550, and am quite happy with the moving map displays, however I also fly in less well fitted out cockpits, and the two ADF needles, are perfect to judge range and bearing to the abm, and even down wind positions. However Mr Garmen has not been teaching this technique recently.!!!!

In another life I also conducted aerial surveys, in a C172, and can vouch for the afternoon story, and womans hour, as perfect foils to a 2 hour orbit.

Until the world demolishes NDB and MW radio facilities, I shall continue to use ALL available facilities to assist SA.

windy

[S-Works]

Well I am glad you are a dying breed, lets hope you don't get a job with the CAA.....

Doing a type rating last few weeks in Canada, the guy teaching us was as old as the wright brothers and had a fascinating career flying everything from body bags in 172's across alaska using LORAN and ADF to Classic 747. He could see no place at all for ADF in this day and age and said that modern airliners that proclaimed to use NDB were actually just using the FMS to point at where the beacon should be. The Garmin can do that just as well.

ADF was a good tool when there was nothing better, just as carbs on cars were before fuel injection. Times change and if we don't change with them there will be nothing left of GA.

I for one won't miss the cost of maintaining a bit of kit that probably gets used twice a year and costs me a fortune to keep working. I have flown one NDB approach for real this year after arriving in Guernsey and the ILS was U/S in my friends Lance that only had steam kit (rectified now with a Garmin fit). The only other time I fly them is my ME/IR renewals.

Joining CAS at WCO is over half my airways joins and I won't miss the needle pointing miles off the track the GNS is giving. Guess what I have never missed WCO with the GPS but I would have many times with the ADF.

[IO540]

There is a slight problem: if overlay approaches were authorised in the UK (which would be great but is highly unlikely) then many IFR approved GPS installations would not be able to use them. My KLN94 uses a version of the Jepp database on which many tracks are missing, and often only the final approach track is shown.

One can still fly the published approach with it of course (it's hardly rocket science) but one would not be getting continuous course guidance in the NAV mode.

[A and C]

ADF as a Backstop

The big problem with GPS is that it is so easy to jam and with the goverment proposing a tax on the free movement of people or road charging as they call it GPS would seem to be the cheapest way to introduce such a tax.

If this comes to pass we will have a great number of people with a very real interest in jamming the GPS system.

So along with the fact that most modern airliners use DME to update the position in the FMS (the B737NG has 5 DME units) I see DME being around for a long time and the logical approach aid to go with this is an ADF located on the airfield as this is the cheapest answer to the GPS jamming issue.

We can also turn this on it's head and oppose the use of GPS for road charging on safety grounds not only for aviation but also for the other safety related uses that GPS has.

[IO540]

a great number of people with a very real interest in jamming the GPS system

Indeed, but the logical thing would be to use a very low power jammer, mounted in the actual vehicle.

Wholesale GPS jamming would stop GPS road navigation which many commercial vehicles rely on totally. It's also impractical; you would need a transmitter suspended under a baloon, or similar. Who is going to bother?

A 1 milliwatt jammer in your car would totally circumvent any road charging scheme but you would have to turn it off if you want to use a GPS for road nav yourself.

[A and C]

IO540

Point taken but what happens when three or four so equiped cars drive under the approach when you are on a CAT 1 WAAS GPS approach?

I dont know the answer but I don't want to find out by trying it !

[IO540]

IMV, universal road charging won't happen precisely because it would be so easy to evade, and road tax works very well.

Should tampering with GPS signals become fashionable, there are some easy countermeasures. I believe this lists some of them.