Using the ADF and NDB together to navigate can seem like a difficult subject, especially when you start reading about it. But, this video explains everything in just a few minutes.
Although NDBs are considered more primitive than VORs, I like that this video shows that, mathematically, you can get the same information. Once a pilot is well-versed in this principle, NDBs can be just as practical, assuming the PIC is aware of the different sources of error in each method.
yes you can use co-located DME with NDB to know the distance but they work on different principles . The NDB frequency is entered in the ADF which is the equipment in the aircraft for NDB ( is the radio station on the ground ) navigation .
Yep normally in an NDB approach one uses a chronometer and groundspeed to know distance flown/remaining. But in the cases you point he should just enter the T-VOR or localizer FQ in the DME box. Actually im not clear if he means measuring distance in flight or during an approach. The technique I gave him involves major heading changes for a sustained time, not practical for an approach or airway flight but its still a basic he should know.
Why use math when one can simply twist the movable card on the ADF so it matches the magnetic compass/heading indication? That way the pilot can track the needle like it was an RMI. The pilot would have to keep twisting the card however so it stays consistent with the given heading, better that than getting confused while flying in clouds.
@DreamVikings. NDB-DME co-installations without VOR do exist in other parts of the world. In Australia we have at Cooma Airport an NDB-DME installation and an approach that used the DME info instead of groundspeed timings. NavAid identifier is COM at ICAO code YCOM and the approach is the NDB-Z RWY 36. You can see the approach plate throughout the Austrailian AIP at the airservicesaustralia.com site. There are others including Moomba NDB-A.
Probably a little late to answer this one, but no. Because you have to point the nose of the a/c into a x/wind by some amout to compensate for drift, the nose of the a/c is no longer pointing at the ndb. The adf needle always points to the tuned ndb, N on the adf is the nose of the a/c, the difference between the two is the number of degrees of drift compensation your applying in order to keep the a/c tracking directly to the ndb.
my bad i might have mislead with my explanation . By saying co-located i meant a terminal NBD and using distance from the DME by with another nearby Navaid. Like using the DME of a T-VOR or of an ILS for an NDB approach .. Some approach charts are named NDB DME Rwy 04 for example and i have seen that . For Navigation i never seen either you are right but for approaches it exits
the video doesnt cover antoher important aspect of the adf needle which is that is suffers from magnetic dip which causes it to turn into the turn from the correct heading (by around +/- 10 degrees when the aircraft is turning.)
Of course, this technique is intended to use in cruise flight, never on an approach. For an approach with ADF one is supposed to use TIME as in a chronometer to know how much distance one has advanced an has remaining based on speed. (with speed and time you can know distance)
How can i get navaid from NDBs in case if i have to land an airport between high rise mountains like OPGT, OPSD. Because if the airport has no charts then hoe NDBs can be helpful?
I dont think it. I never seen a NDB linked to a DME. Usually VORs are linked to DME, not NDBs. There is a formula to know your distance to the NDB based on your ADF readings and speed. I can explain if you are intrested.
@@sagu925 Well it is hard to explain in words, but imagine you have your NDB and your ADF needle is pointing to it. You turn left or right. Lets say right. (yes, you need to turn, because you need the adf needle pointing almost 90% to a side) Leave the needle 5 degrees above directly pointing to your right. As you keep flying straight, the needle will drop slowly. Needle always drops. Eventually it will be completely 90ªs to your right, because the NDB station is also 90º directly to your right. Start your chrono. Keep it running for 20 or 30 secs. Write down how much time and how much degrees of change for the needle. Formula is time(seconds) / degrees of needle movement = Minutes to the station if you were flying towards it. Ie took 30 seconds for the needle to drop 10 degrees. 30/10=3 minutes With this time and your groundspeed you should be able to also calculate the distance. Of course, this does not account for wind. Its a pretty ancient rule of thumb technique.
