Minimum Instruments For IFR/IMC
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Thanks
thanks for all the input into the discussion. Looks like an ADF is required: For transits/landings IFR in zones and as there are so many procedures out there that still use them.
I certainly tune it in as a back up when flying. But then again I still draw a line on a map and use the GPS to check it!
I certainly tune it in as a back up when flying. But then again I still draw a line on a map and use the GPS to check it!
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I know technology has moved on but I used to get great satisfaction out of being able to complete a plus/minus 10 second NDB hold and approach
The protected area of a hold is massive - big enough for a 747 at something like 200kt. Consequently there is exactly zero point in flying one to the accuracy you refer to. It may be fun but a pilot doing that - no matter how good he is - isn't going to have spare brain capacity to keep tabs on everything else he needs to do. Let's say that on hold #7 the surface wind changes resulting in a runway change and he has to dig out a bunch of the 'other' approach plates, while flying this wonderfully perfect NDB hold. The whole job is going to come to pieces - because he had no spare brain capacity. Better still, his fuel goes below reserves while in the hold and then he has to do something else.
The 'art' of flying safely is to manage the cockpit workload so it is minimised, and then you can handle whatever ATC or weather throw at you.
Funnily enough I quite like the ADF - when I used to fly VFR abroad, it made a handy backup for the GPS because very often there were no VORs on the route (the VORs were in CAS). I have a dual-needle RMI displaying the ADF bearing and flying NDB-anything is a piece of cake. But if you look at the cost of a modern reliable ADF (and there is only the KR87 - the rest is nearly all unreliable junk) it's a good few grand and this is not justified against other kit you could spend that sort of money on. The ADF is also very inaccurate, with 30 degree errors (within a specific close range to the beacon, say between 3nm and 5nm) being common.
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IO
I think you're trying to tell me that you can't handle the cockpit load - just joking. I thought that teaching the ADF/NDB hold was a good exercise for a student as it taught them about cockpit scan and discipline. Of course these days you can get the autopilot to do it all for you. I flew around Australia a couple of years back, some of the NDBs had a 150 mile range and it was interesting to compare it with the GPS. I agree the cost of ADF equipment is out of proportion with other types of kit and that the KR87 is probably the best available at the moment.
I think you're trying to tell me that you can't handle the cockpit load - just joking. I thought that teaching the ADF/NDB hold was a good exercise for a student as it taught them about cockpit scan and discipline. Of course these days you can get the autopilot to do it all for you. I flew around Australia a couple of years back, some of the NDBs had a 150 mile range and it was interesting to compare it with the GPS. I agree the cost of ADF equipment is out of proportion with other types of kit and that the KR87 is probably the best available at the moment.
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Well yes but you are moving the goalposts 
Long range enroute nav works pretty well with NDBs because the field distortion caused by coasts and terrain tends to be only local to the beacon, so if you are 100nm away from the beacon, it will be accurate. On my system I have found enroute NDB nav to be more or less as accurate as VOR tracking. I can see the old NDBs, radiating tens of kW, worked very well in the old days, and there were no VORs.
And anybody with the briefest training can enroute track towards an NDB. Especially when enroute when there isn't normally much to do.
But earlier on you talked about NDB holds. These, especially if flown with the 'gates' beloved by IR examiners, are just plain hard work.
Autopilots don't come into this, though obviously they drop cockpit workload by an order of magnitude. But I think that if somebody has an AP, they probably also have a GPS....
And very few GA autopilots can fly holds. Only the relatively modern kit can. You need something like a GNS430W or 530W, driving an AP via ARINC, to fly holds - especially if you want it to compute and fly the correct pattern entry. My AP can fly anything but the KLN94 GPS doesn't contain holding patterns or even (in Europe) any curved tracks.
If I had to fly a hold (only about once in last few years) I would use the OBS mode of the GPS to give me the inbound track on the screen, and then twiddle the heading bug.
Long range enroute nav works pretty well with NDBs because the field distortion caused by coasts and terrain tends to be only local to the beacon, so if you are 100nm away from the beacon, it will be accurate. On my system I have found enroute NDB nav to be more or less as accurate as VOR tracking. I can see the old NDBs, radiating tens of kW, worked very well in the old days, and there were no VORs.
And anybody with the briefest training can enroute track towards an NDB. Especially when enroute when there isn't normally much to do.
But earlier on you talked about NDB holds. These, especially if flown with the 'gates' beloved by IR examiners, are just plain hard work.
Autopilots don't come into this, though obviously they drop cockpit workload by an order of magnitude. But I think that if somebody has an AP, they probably also have a GPS....
And very few GA autopilots can fly holds. Only the relatively modern kit can. You need something like a GNS430W or 530W, driving an AP via ARINC, to fly holds - especially if you want it to compute and fly the correct pattern entry. My AP can fly anything but the KLN94 GPS doesn't contain holding patterns or even (in Europe) any curved tracks.
If I had to fly a hold (only about once in last few years) I would use the OBS mode of the GPS to give me the inbound track on the screen, and then twiddle the heading bug.
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cjboy
I am always pleased to be of assistance but it is not your flying technique that I am seeking to improve!
You would certainly make a fascinating addition to a CRM course, the moment that someone suggests a way of looking at things you instantly think that they are "having a go" at you personally, (rather than the training system and general stick in the mud attitude of the UK regulatory authority that has (mis?)programed your brain).
Last night out of pure interest I did an NDB approach using the company SOP. the ADF was tuned and selected but with two FMC's three ADIRU's two GPS's five DME's and three VOR's doing all the thinking just how much input did the ADF have into the management of the approach?.
The answer of course it that the ADF had absolutely no input what so ever in the positioning of the aircraft either vertically of laterally and to all intents and purposes the aircraft was on an RNAV approach with the ADF selected to stay legal.
Fortunately I don't have to fly under UK CAA regulation as last nights fully managed approach (I am told) is still not approved by them despite the aircraft being on the UK register for twenty years, Flying with company's that are regulated by authority's that don't have the head in the sand attitude of the CAA had been a real eye opener into the potentials for safety improvement.
The only criticism that I would level at you (and only on the basis of two or three posts on this forum) is that you don't seem to have an open mind to other ways of looking at things, but perhaps you are a victim of he CAA controlled training, I know that until I got out into the big wide world I to had an attitude that was narrowed by my UK training.
You would certainly make a fascinating addition to a CRM course, the moment that someone suggests a way of looking at things you instantly think that they are "having a go" at you personally, (rather than the training system and general stick in the mud attitude of the UK regulatory authority that has (mis?)programed your brain).
Last night out of pure interest I did an NDB approach using the company SOP. the ADF was tuned and selected but with two FMC's three ADIRU's two GPS's five DME's and three VOR's doing all the thinking just how much input did the ADF have into the management of the approach?.
The answer of course it that the ADF had absolutely no input what so ever in the positioning of the aircraft either vertically of laterally and to all intents and purposes the aircraft was on an RNAV approach with the ADF selected to stay legal.
Fortunately I don't have to fly under UK CAA regulation as last nights fully managed approach (I am told) is still not approved by them despite the aircraft being on the UK register for twenty years, Flying with company's that are regulated by authority's that don't have the head in the sand attitude of the CAA had been a real eye opener into the potentials for safety improvement.
The only criticism that I would level at you (and only on the basis of two or three posts on this forum) is that you don't seem to have an open mind to other ways of looking at things, but perhaps you are a victim of he CAA controlled training, I know that until I got out into the big wide world I to had an attitude that was narrowed by my UK training.
