fixed card adf

[rigobgo]

I am trying to figure out 2 questions on fixed card adf.

1. Your heading is 070 degrees M and relative bearing to NDB station is 340 degrees. In order to intercept a track of 300 degrees M outbound from the NDB at 45 degrees, what initial heading is required?

2. Upon intercepting the required track, what relative bearing will the needle, on the fixed card ADF, indicate?

Thanks in advance to anyone who can shed some light on this.

[Tail-Chaser]

If I can still do this right, it should be 345 on the heading.

Once you're on the outbound track, the relative bearing needle should be at 180.

[rigobgo]

the first answer is correct 345 but can you explain how you got it?

the second answer should be 135.

[Tail-Chaser]

Okay, I see what they did there. I assumed that you'd turn to track outbound.

The first answer is 345 based on your position relative to the NDB.

I usually draw a diagram for questions like these. You're on heading 070, and the your relative bearing is 340, meaning it's 20 degrees off to your left. If the NDB was directly north when you're on a heading of 070, your relative bearing would be 290. It works out that you're basically to the Southwest of the station, so to intercept 300 at 45 degrees, all you have to do it tack 45 degrees onto 300. A lot of intercept questions work like this.

The reason it's 135 for the second, is that on a heading of 345, you're 45 degrees off the outbound track, with the station behind and to the right of your tail, making your relative bearing 180-45 = 135. As soon as you turned to track outbound the relative bearing would be 180.

[fabichoux]

To intercept an outbound track, use the following formula:

Tail-Desired-Further

Pick the tail of the needle (which is at 160) (head at 340)

Move the tail toward the desired track (300) by the shortest path (160 -> 300)

Futher, move 45deg further (you want to intercept with a 45deg angle, so 345deg..

Thats it.

On the 300 outbound track, the needle will be on 135... (you intercept with a 45 deg angle) (180-45=135)

About the same for an an inbound track, but the formula is:

Desired-Head-Further...

From the desired track on your ADF, move toward the head of the needle and X deg further for the intercept!!!

Example: you want track 030, you are on 000. (ADF is on 0)

On the ADF, pick the 030 (desired), move toward the head (000) (030 -> 000)

Then 30 deg further (000 -> 330)

So head 330 to intercept track 030.


Have fun

[Independence]

I find it ironic that Transport Canada makes commercial operators teach their pilots specific GPS courses if they are going to do GPS IFR but we can do fixed card ADF approaches without any ground school requirements.

[fish4life]

A better question is who still uses one for IFR ?

[Big Pistons Forever]

A better question is who still uses one for IFR ?

How else are you going to listen to vintage Rock and Roll courtesy of the best of AM radio, when you are droning along in cruise autopilot on and bored out of you skull ?

[Shiny Side Up]

How else are you going to listen to vintage Rock and Roll courtesy of the best of AM radio, when you are droning along in cruise autopilot on and bored out of you skull ?

I don't think there's anything that plays music on AM radio around here anymore. The only things you can get on the ADF are how badly the Flames got shellacked the previous nite and the current going price on hogs. Ah, for the good ol' days of AM radio.

[Colonel Sanders]

KR87 is the best $5,000 timer I've ever used!

[Meatservo]

A better question is who still uses one for IFR ?

I last used one for a real instrument approach about five years ago. Made a real dog's breakfast of it, too.

I find however, I've experienced a bit of a resurgence in the technique, not fixed-card, but with these new DRMI thingies that sometimes come with the GPWS kit... In VFR operations where the visibility might not be as good as you've hoped you can use a user-defined waypoint, and on the DRMI you can make a needle appear which points at your waypoint. Now using the same techniques as you may have learned for NDB navigation you can approach your waypoint on any desired track.. I find it augments situational awareness. Of course you can do the same thing mentally using the "BRG" and "TRK" info in the GPS screen the same way. Or "OBS" mode...still, even on a purely GPS-based approach in IFR, I find it helpful to have the GPS waypoint brought up on the RMI "screen".

I'm not sure if I find this useful because it actually is helpful, or whether I am just comfortable with it because I learned radio navigation the old-fashioned way. Still, I feel that practicing building situational awareness using old forms of navigation, or adapting them to new technology, keeps my brain busy and sometimes I find interesting ways to use the old-fashioned techniques to interpret modern information. When I look at bearing/track information on a GPS screen, I can actually mentally picture an ADF and it helps with situational awareness, for me anyway.

Sorry if I caused the thread to drift.

[iflyforpie]

In real life, you should never have to worry about a fixed card ADF. Look at the needle, transpose it over to the HSI/DG.... you now have a poor man's RMI. I couldn't imagine doing those calculations in the air.

I've got two fixed card and one movable card ADF. Actually, the one is so old it says 'Radio Compass'. They all work and I use them all of the time VFR; quicker for a direct to an airport than selecting and punching in all of the identifiers on my ancient GPS. My King one is an ancient ADF-T-12C... so it isn't even good as a timer unfortunately.

[Shiny Side Up]

In real life, you should never have to worry about a fixed card ADF. Look at the needle, transpose it over to the HSI/DG.... you now have a poor man's RMI. I couldn't imagine doing those calculations in the air.

This is what I've always done as well, for some reason some people just can't do this though and is the reason someone came up with all of those means of doing math. I suppose one might have had to do that with a fixed card ADF and a Puck style DG. That's some pretty primitive shit to fly an approach with these days, I couldn't reccomend if one has any way of avoiding.

[iflyforpie]

I suppose one might have had to do that with a fixed card ADF and a Puck style DG. That's some pretty primitive shit to fly an approach with these days, I couldn't reccomend if one has any way of avoiding.

A puck style DG...? Oh man, I've got so much more respect for Cat Driver now!

[fish4life]

Ya the adf RMI's are still a great tool

[Colonel Sanders]

My King one is an ancient ADF-T-12C

I didn't know anyone used those any more. They
were really good, a very long time ago.

[Siddley Hawker]

How else are you going to listen to vintage Rock and Roll courtesy of the best of AM radio, when you are droning along in cruise autopilot on and bored out of you skull ?

+1 Hell, years ago on our late sched from Schefferville we used to phone in requests to WABC.

[Panama Jack]

What's an ADF? Oh, it is those things they still use in Canada. Canada, you say??? Pity!!!

[Cat Driver]

A puck style DG...? Oh man, I've got so much more respect for Cat Driver now!

Yeh, I remember the unbelievable jump in technology for doing approaches when we went from riding the twilight zone of the radio range and making a perfect pass through the cone of silence to having the modern puck style DG and a fixed card ADF in the DC3's.

Shot hundreds of approaches in IMC to unprepared ice strips with flare pot lighting in weather that had polar bears dug in to escape the storm.

But I am from the days of the wooden ships and the iron men.

Oh, we measured x/wind limits by the simple method of if the x/wind component was more than 50% of our cruise ground speed we usually did not try and land.

[iflyforpie]

But.... isn't 50% of the cruise velocity of the PBY somewhat below the maximum demonstrated cross wind component for a 172?

[Cat Driver]

We never flew PBY's in the winter in the Arctic Ifly, we flew DC3's in the winter.

The strongest x/wind that I recall landing a DC3 in was 50 knots at 90 degrees to the runway at Resolute Bay....in zero/zero visibility in blowing snow....FSS gave us the numbers on close final.

And in those days we could fly any type of airplanes that a company owned, all we had to do was show the chief pilot we could actually fly them... I flew for a company in Windsor Ont that had a pile of different airplanes both single engine and twins plus two different helicopters. I flew whatever machine that was needed day after day with no problems, and then after work I rode my motorcycle home and no PPC on any of them.

...PPC's did not exist...

Today it is different because due to TC's vision of what pilots can do most working pilots are one trick ponies due to PPC's.

[vcollazo]

AM 740 out of Toronto plays a lot of 50s and 60s rock as well as big band. I used to listen to them all the time when I flew the DC9. At night you can get them on the ground as far south as North Carolina and as far west as western Ohio. They have a mighty powerful transmitter.

[Old fella]

Many years back working in Maritimes departing out of YWK for YYT we would be over ole Lake Eon(or before) and could always get VOCM 590 in YYT - good tunes then as well.

[switchflicker]

Interesting how the thread went from flying with a fixed card ADF to how many types of aircraft and motorbikes one could fly in a day.

Anyone else try to fly multiple types of sofisticated aircraft, ones with instruments and electronics and stuff, all in one day without training. Just a nod from the CP.

[Cat Driver]

Anyone else try to fly multiple types of sofisticated aircraft, ones with instruments and electronics and stuff, all in one day without training. Just a nod from the CP.

This is an aviation discussion forum.

My comment was to point out that I was fortunate to have flown in an era when we were not relegated to one trick ponies mandated to only fly only the airplanes you have a PPC for.

But hey whatever floats your boat, at least I have lived and flown in both eras and as a pilot I preferred the earlier days of this industry.

It is that simple.

ones with instruments and electronics and stuff,

We flew auto parts at night in the Beech18 and the Dehavilland Dove mostly from Ontario into and out of Chicago O'hare airport...they required us to have instruments and electronics.......maybe our instruments and electronics were not a smart as you people have today......but that also says something.