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ETOPS773
22nd Oct 2003, 01:40
Hello,
I`m currently about 3.5 hours into my IMC and doing it in a well equipped PA28.

The ADF in it is rotatable card type, but I`m being told that I must not touch it and must leave it pointing north all the times.

This is a pain...rotatable card is much beter,easier..we all know the score.

Is there any good reason for leaving it pointing north all the time? is it a requirement??

Cheers.

Send Clowns
22nd Oct 2003, 03:25
I agree that for plotting from an NDB a magnetic bearing is more useful, but you title the thread "ADF tracking", and assuming you have a good idea of hte wind tracking inbound (or outbound to some degree) to an NDB all you are concerned with is drift. Absolute bearings are not as important. I never did hte IMC, so am not sure whether you are supposed to be tracking a given bearing or just tracking towards the beacon.

MEI
22nd Oct 2003, 05:12
I used the same method with my students. I told them to leave the card alone. This is because if you forget to turn the card one time your reading the wrong bearings. I always taught to just use it as a poor man's RMI. Where you just visually put the neddle on your DI. In a high workload of IFR it's just another distration when your a student. This was FAA IR's though not sure about the IMC because I've never done one. That maybe what your instructor is eludeing to.

GT
22nd Oct 2003, 19:54
ETOPS773,

There's little point in learning how to use an RBI by rotating it's card, and the reason is simple. You're going to have to interpret what it is telling you when you're turning in the hold, flying base turns, procedure turns, missed approach turns, etc. In other words, you're going to need to be able to use it when turning to see if the turn is going according to plan. It would be impractical, if not impossible, to continually rotate the RBI card to match the DI whilst flying a turning aeroplane. Rotating the RBI card may seem the obvious answer in the early stages of your training but it will leave you short of the mark later. Hope this helps.

Regards, GT.

IO540
24th Oct 2003, 00:14
GT

I would agree entirely except that in many training planes the retrofitted ADF is about 3 feet away from the DI :O - right over where the instructor is sitting.

It has been described to me (by an instructor) as one of the fringe benefits with a female student...

clubhouse
25th Oct 2003, 16:34
Learn to superimpose the ADF needle onto the DI, it sounds hard but if you try you will learn it really quickly. After a while you can just glance at the two instruments and see them as one.

Pilotbear:cool:

Tinstaafl
26th Oct 2003, 06:47
Get used to fixed card usage. It's very, very easy to switch to an RMI but not so easy the other way round. Bear in mind that even if the primary ADF is an RMI the secondary may be a fixed card mounted on the far side of the panel ( that's the case for our fleet).

IO540
4th Nov 2003, 03:13
You have an RMI in your training planes?? An RMI is a slaved ADF or VOR needle indicator, with the OBS slaved to a wingtip fluxgate magnetometer. An ADF with a manually rotating card isn't an RMI, AFAIK. A real RMI is very expensive; usually comes with a slaved HSI also.

Tinstaafl
4th Nov 2003, 04:26
IO540, all our piston a/c use HSIs, RMIs + 2nd boxes as 'standard' OBS/CDI or rotatable ADF. But they're not used for training other than the required checks & training stuff.

I think ETOPS773 is referring to a rotatable ADF card - but trying to use it as a 'poor man's RMI' ie keep manually adjusting it to sync with the DI. NOT a good way of doing it.

Most of us seem to agree that learning to use the fixed cards method for that type of display is the better way. Many of us also seem to agree that it's easier to move from fixed to RMI use than the reverse.

My comments also referred to quite common setups out in the wild where RMI 'everything' is not particularly common eg my mob. Sorry if I wasn't as clear as I should have been.