The end of ADF at last?
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The end of ADF at last?
I read in the latest copy of AOPA's General Aviation that the CAA is finally going to give up the ADF as a requirement for IR in UK controlled airspace. Anyone know the details?
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What on earth do have against the poor ADF? OK it has its limitations but its beauty lies in its simplicity. There is something very comforting about having a needle that points home.
Ducking from those who'll accuse me of living in the past and obstructing progress! But remember the ultimate goal of progress in aviation is total safety. And that means the end of the weakest link in the chain. You and me. I don't know about everyone else, but I enjoy hands on flying, get great satisfaction on the odd occasion I do it well. Taking the challenge away, takes away the fun!
Ducking from those who'll accuse me of living in the past and obstructing progress! But remember the ultimate goal of progress in aviation is total safety. And that means the end of the weakest link in the chain. You and me. I don't know about everyone else, but I enjoy hands on flying, get great satisfaction on the odd occasion I do it well. Taking the challenge away, takes away the fun!
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ADF
What do I have against ADF? How about the time when I did a practice NDB approach (fortunately not under real IFR) into Gloucester some years ago to find the ADF needle pointing 180 degrees the wrong way. It was being interfered with I believe by a radio station in France.
Blah Blah Blah
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The ADF or NDB as it is better known is great! old but simple. With the inception of VOR's the NDB has been forced to take a back row seat. A bit like good ole map, compass and stop watch has been canned by anyone who owns a GPS!.
NDB with a DME is perfectly adequate and I will be sad to see it go.
Maybe you all think I am sad to want to see it stay.
NDB with a DME is perfectly adequate and I will be sad to see it go.
Maybe you all think I am sad to want to see it stay.
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The ADF system is quite good for the purpose for which it was developed around the time of WW2: providing crude but usable guidance for long distance flying. The NDB transmitter is a simple thing to make and to keep going, and the more kilowatts you pump into the bottom of it the longer its range will be. It works well over flat open country, the sea, and over long ranges (hundreds or even - with huge amounts of power - thousands of miles).
I routinely tune in an NDB when flying long VFR legs across e.g. France, for both backing up the primary nav (GPS) and to give me a well known clear waypoint for the flight plan. I do this a lot less now because I do long flights under IFR and IFR (airways) is all GPS - GPS (RNAV) is in fact mandatory.
Unfortunately NDBs have gone out of fashion for enroute nav a long time ago, due to VORs and more recently GPS, and tend to be used mostly for instrument approaches, and that is where they fall down badly. When you are close to the beacon, say tens of miles or less, you are entering the part of its radiation pattern which is affected by terrain/coast assymetry, electrical storms, god knows what else, and it's easy to find one's track 30 degrees off. The approach designers know this of course so NDB approaches are designed with loads of latitude for lateral errors, often using DME to ensure that if the radiation is disrupted so badly you end up way off track (but have followed the DME stepdowns) you will probably not hit any hills (but may not be able to land, which is "OK"), but the end result is an instrument approach with a decision height like 800ft which is basically useless for the average British Warm Front kind of weather...
Airliners use inertial navigation now, the new ones with GPS, and they totally ignore NDBs enroute. They also tend to ignore NDBs on approaches, flying the approach using the INS (FMS) and only checking the NDB at the start. However I think there are enough dual-NDB approaches in Russia to keep the ageing CAA ATPs happy
To top it, of all the avionics you can stuff into a GA plane, the ADF is probably the least reliable. The current KR87 is generally OK but most of the others were crap, and expensive to repair. It is common to find, on the average spamcan, that the ADF is duff and nobody wants to pay the £3000+ to get it fixed.
AFAIK the current proposal is to do away with the requirement for the ADF for IFR in CAS i.e. enroute. Most European countries never had such a requirement in the first place - it's a peculiarly British=Superior thing - and just looks plain silly.
I don't see the ADF going away on instrument approaches in Europe, where it is widely used as a locator.
I would keep my ADF working but won't be sorry to see enroute NDBs disappear.
I routinely tune in an NDB when flying long VFR legs across e.g. France, for both backing up the primary nav (GPS) and to give me a well known clear waypoint for the flight plan. I do this a lot less now because I do long flights under IFR and IFR (airways) is all GPS - GPS (RNAV) is in fact mandatory.
Unfortunately NDBs have gone out of fashion for enroute nav a long time ago, due to VORs and more recently GPS, and tend to be used mostly for instrument approaches, and that is where they fall down badly. When you are close to the beacon, say tens of miles or less, you are entering the part of its radiation pattern which is affected by terrain/coast assymetry, electrical storms, god knows what else, and it's easy to find one's track 30 degrees off. The approach designers know this of course so NDB approaches are designed with loads of latitude for lateral errors, often using DME to ensure that if the radiation is disrupted so badly you end up way off track (but have followed the DME stepdowns) you will probably not hit any hills (but may not be able to land, which is "OK"), but the end result is an instrument approach with a decision height like 800ft which is basically useless for the average British Warm Front kind of weather...
Airliners use inertial navigation now, the new ones with GPS, and they totally ignore NDBs enroute. They also tend to ignore NDBs on approaches, flying the approach using the INS (FMS) and only checking the NDB at the start. However I think there are enough dual-NDB approaches in Russia to keep the ageing CAA ATPs happy
To top it, of all the avionics you can stuff into a GA plane, the ADF is probably the least reliable. The current KR87 is generally OK but most of the others were crap, and expensive to repair. It is common to find, on the average spamcan, that the ADF is duff and nobody wants to pay the £3000+ to get it fixed.
AFAIK the current proposal is to do away with the requirement for the ADF for IFR in CAS i.e. enroute. Most European countries never had such a requirement in the first place - it's a peculiarly British=Superior thing - and just looks plain silly.
I don't see the ADF going away on instrument approaches in Europe, where it is widely used as a locator.
I would keep my ADF working but won't be sorry to see enroute NDBs disappear.
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What is it that will be done away with, the NDBs, the approaches or the ADF kit in the aircraft? Sounds to me that it simply means that there will be no requirement to have a (servicable) ADF fitted to fly IFR in controlled airspace. It would be a shame to loose the NDB network, if nothing else because it is such a great gross error check. I have to say that I have never had the inaccuracies or unserviceabilities experienced by others here and the MDHs I use seem to be about 450' which are still reasonably useful.
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Would this have something to do with pressure from Cirrus/Garmin?
When the Cirrus first came out with the glass cockpit based on the G-1000, I believe they could not get the combination certified for IFR airways (in the UK only) because of the UK-only requirement to carry an ADF. So they had to put a 19th century ADF in an otherwise 21st century cockpit. And, obviously, none of the drivers actually used the ADF, possibly except for training, because it wasn't integrated with the G-1000 like the other NAV instruments (GPS, VOR, ILS, DME, marker). Very expensive ballast. I have no doubt that Cirrus and the other a/c manufacturers that use the G-1000 (or any of its competitors), plus the drivers of these machines, do not regret seeing the requirement disappear.
I would also imagine that the law says something like you can only plan and execute a flight for which you are suitably equipped. So if the planned flight ends in IMC, at an airport which only has an NDB approach, then, by law, for that flight you need an ADF anyway - or make a different plan. Nothing new there really.
As for using NDBs enroute: yes, it's a shame that they are disappearing, but we GA have to remember that we are making free use of an infrastructure which is mostly installed, maintained and used for/by the commercials. If they have no need anymore for it, then either we have to find a way to convince the authorities to keep them in place, or pay for them ourselves.
When the Cirrus first came out with the glass cockpit based on the G-1000, I believe they could not get the combination certified for IFR airways (in the UK only) because of the UK-only requirement to carry an ADF. So they had to put a 19th century ADF in an otherwise 21st century cockpit. And, obviously, none of the drivers actually used the ADF, possibly except for training, because it wasn't integrated with the G-1000 like the other NAV instruments (GPS, VOR, ILS, DME, marker). Very expensive ballast. I have no doubt that Cirrus and the other a/c manufacturers that use the G-1000 (or any of its competitors), plus the drivers of these machines, do not regret seeing the requirement disappear.
I would also imagine that the law says something like you can only plan and execute a flight for which you are suitably equipped. So if the planned flight ends in IMC, at an airport which only has an NDB approach, then, by law, for that flight you need an ADF anyway - or make a different plan. Nothing new there really.
As for using NDBs enroute: yes, it's a shame that they are disappearing, but we GA have to remember that we are making free use of an infrastructure which is mostly installed, maintained and used for/by the commercials. If they have no need anymore for it, then either we have to find a way to convince the authorities to keep them in place, or pay for them ourselves.
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ADF
I assume that what the CAA intends is to remove the REQUIREMENT to have ADF while flying IFR in controlled airspace, and at this time no suggestion that NDB's will become unavailable (although I am pretty sure that eventually that will happen too).
By the way, the ADF is the thingy you have in the aircraft while the NDB is the thingy on the ground that transmits a radio signal: they are not the same thing.
With modern GPS systems and PDF's one can now have a bearing indciator pointing to wherever you want which looks to all intents just like an ADF RMI. The only difference from a true ADF is that it is not actually in receipt of the radio signal ( together with all its well known errors) and there is no dip error. This makes a vastly superior, simpler to use, and more precise effective ADF than a true ADF. It does seem to me that one should be allowed to substitute this for an ADF in order to perform an NDB approach where at present there are no official GPS approaches. In due course I would expect in any case NDB approaches to disappear and be replaced entirely by GPS approaches.
By the way, the ADF is the thingy you have in the aircraft while the NDB is the thingy on the ground that transmits a radio signal: they are not the same thing.
With modern GPS systems and PDF's one can now have a bearing indciator pointing to wherever you want which looks to all intents just like an ADF RMI. The only difference from a true ADF is that it is not actually in receipt of the radio signal ( together with all its well known errors) and there is no dip error. This makes a vastly superior, simpler to use, and more precise effective ADF than a true ADF. It does seem to me that one should be allowed to substitute this for an ADF in order to perform an NDB approach where at present there are no official GPS approaches. In due course I would expect in any case NDB approaches to disappear and be replaced entirely by GPS approaches.
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With modern GPS systems and PDF's one can now have a bearing indciator pointing to wherever you want which looks to all intents just like an ADF RMI
True, but TBH I doubt that if the GPS was invented in WW2 anybody would be using "needles" today. The CDI/RMI/HSI bar or needle representation dates back to the goode olde days when a map type representation was technologically all but infeasible, and clever people invented all kinds of ways to enable planes to navigate relative to beacons.
Today, if really using the GPS, you would dial the inbound on the OBS mode of the GPS and track the magenta line (inbound) or the white line (outbound).
True, but TBH I doubt that if the GPS was invented in WW2 anybody would be using "needles" today. The CDI/RMI/HSI bar or needle representation dates back to the goode olde days when a map type representation was technologically all but infeasible, and clever people invented all kinds of ways to enable planes to navigate relative to beacons.
Today, if really using the GPS, you would dial the inbound on the OBS mode of the GPS and track the magenta line (inbound) or the white line (outbound).
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It is interesting to note that none of the brigade that will be sad to see ADF go are actually serious IR flyers.
Everyone of us with an IR flying proper IFR all the time cant wait to see the back of the NDB/ADF kit and that none of us actually fly pure NDB approaches and all use the GPS overlay.
As IO540 points out ADF was made for a day one nothing else was available, now the military would not even consider its use.
Everyone of us with an IR flying proper IFR all the time cant wait to see the back of the NDB/ADF kit and that none of us actually fly pure NDB approaches and all use the GPS overlay.
As IO540 points out ADF was made for a day one nothing else was available, now the military would not even consider its use.
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No one seems to have mentioned the main use of the NDB (The ground station cost about half-a-crown a week to maintain) It is ideal for situational awareness during the initial approach phase, ie if the radar controller has forgotton about you, which I've experienced a few times, or just knowing where you are at a glance during prolonged radar vectoring, especially when adjacent to lumps of rock. It helps to keep the flight deck in contol. When STN ditched the SAN, it wasn't long before pilot pressure had an NDB reinstated.
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Spot on croqueteer and sadly the GE and GY have been withdrawn at LGW simultaneously.Mine seems to have been the lone voice raised in protest (sign of changing times and generations).No sign yet of a single airfield located replacement which is a happy compromise,there dores not seem to be a head of steam! in protest.So now total reliance on the radar controler to get you on the correct centreline and far less situational awareness.
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total reliance on the radar controler
What about looking at the GPS moving map? That tells you exactly where you are.
The NDB or the ADF could fail and the fault may not be evident; the needle will always point somewhere on the 360 deg circle. The morse code ident only proves the frequency tuner is demodulating the AM portion with the ident on it; it says nothing about the rest of the instrument.
What about looking at the GPS moving map? That tells you exactly where you are.
The NDB or the ADF could fail and the fault may not be evident; the needle will always point somewhere on the 360 deg circle. The morse code ident only proves the frequency tuner is demodulating the AM portion with the ident on it; it says nothing about the rest of the instrument.
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LGW's GE/Y are to be replaced with an on site NDB (Glasgow style) according for our fleet manager.
Serious IFR stuff - ADF's are invaluable in a steam driven cockpit. The simplicity of the system and the situational awareness that it gives you (particularly when tied to a DME) in a glance can not be understated. With a glass flight deck with map displays they largely become the third glance rather than the first. BUT, when the map displays go up the swanny, guess which needle you will be searching for first...I know, been there!
Serious IFR stuff - ADF's are invaluable in a steam driven cockpit. The simplicity of the system and the situational awareness that it gives you (particularly when tied to a DME) in a glance can not be understated. With a glass flight deck with map displays they largely become the third glance rather than the first. BUT, when the map displays go up the swanny, guess which needle you will be searching for first...I know, been there!
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Having recently watched a presumably overloaded commercial flight (ME piston) climb only about 500 feet some 5nm after departure, it should come as no suprise to me that there are commercial operations which rely on the ADF needle "especially when adjacent to lumps of rock", but I hope that I never end up sitting in the back of one of them, Croqueteer.
If you really rely on the ADF needle "especially when adjacent to lumps of rock" then presumably you don't carry an EGPWS either.
I agree that every bit of situational awareness helps (and I use the ADF needle on the RMI too) but IMHO you are just trying to justify some of the dinosaur hardware that is still flying "commercially". Of all the stuff one can screw into one's panel, the ADF is the last thing I would rely on for obstacle clearance.
Dyson - the proposal, AIUI, is to do away with the mandatory ADF for IFR in UK CAS, which is basically airways flight, and you can't fly airways without BRNAV capability, which in the GA context means a mandatory IFR GPS. In Class G, it won't worry you.
If you really rely on the ADF needle "especially when adjacent to lumps of rock" then presumably you don't carry an EGPWS either.
I agree that every bit of situational awareness helps (and I use the ADF needle on the RMI too) but IMHO you are just trying to justify some of the dinosaur hardware that is still flying "commercially". Of all the stuff one can screw into one's panel, the ADF is the last thing I would rely on for obstacle clearance.
Dyson - the proposal, AIUI, is to do away with the mandatory ADF for IFR in UK CAS, which is basically airways flight, and you can't fly airways without BRNAV capability, which in the GA context means a mandatory IFR GPS. In Class G, it won't worry you.
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Bose,
I do hold an IR and do use it. I have been compelled to use NDBs alot, due to the type of flying that I do. Enroute, we rely on a (non moving map) GPS. It's ok. But its a long way outwith the standard scan, so we don't even look at it for approaches. NDBs allow us a level of capability that would not be improved upon if we were to use GPS for approaches. Yes a fancy moving map properly integrated into the instrument fit would make life easier but it would also mean that my IF and spatial awareness skills will degrade through lack of use.
It's horses for courses. Aviation is wonderfully diverse - we all fly different machines in different roles for different rewards. To generalise is inappropriate.
Progress will ultimately turn an airline pilot into a customer service role. The pilotless airliner is almost here. Private flying offers the opportunity to preserve proper flying skills - look how many airline pilots swap their nice big air con quiet cockpits for a smelly old string bag or cramped glider? Please don't demean others by assuming we all want progress in private flying.
I do hold an IR and do use it. I have been compelled to use NDBs alot, due to the type of flying that I do. Enroute, we rely on a (non moving map) GPS. It's ok. But its a long way outwith the standard scan, so we don't even look at it for approaches. NDBs allow us a level of capability that would not be improved upon if we were to use GPS for approaches. Yes a fancy moving map properly integrated into the instrument fit would make life easier but it would also mean that my IF and spatial awareness skills will degrade through lack of use.
It's horses for courses. Aviation is wonderfully diverse - we all fly different machines in different roles for different rewards. To generalise is inappropriate.
Progress will ultimately turn an airline pilot into a customer service role. The pilotless airliner is almost here. Private flying offers the opportunity to preserve proper flying skills - look how many airline pilots swap their nice big air con quiet cockpits for a smelly old string bag or cramped glider? Please don't demean others by assuming we all want progress in private flying.