Ordinarily, VFR flights will at least begin in good weather conditions. Most often it is only after the flight progresses from good weather into deteriorating weather and the pilot "continues" in the hope that conditions will improve, that the need for navigational help arises. Since the area from which the pilot came is where the good weather was, naturally it is advisable to turn around and head back to that area when deteriorating weather first is encountered. In most cases there will be some type of radio navigation aid available to help the pilot return to the good weather area. Unless hopelessly disoriented, the pilot should determine the location and transmitting frequency of a VOR or NDB (ADF) that can be used for guiding the airplane back to the better weather area.
When a VOR is chosen, the omnireceiver should be tuned to the assigned frequency of the selected VOR station. After the station is identified the omnibearing selector should be turned until the TO/FROM indicator shows TO and the course deviation needle is centered.
The omnibearing selector then will be indicating the magnetic
course to fly directly to the station. The airplane then should be turned
to the corresponding magnetic heading, and heading adjustments made as
required to follow the course to the station. Procedures for maintaining
the course are explained in the chapter on Cross-Country Flying.
If an NDB is to be used, the ADF receiver should be tuned to the frequency of the selected NDB and the station positively identified. Then the airplane should be turned until the ADF pointer is on the nose position of the instrument. Keeping the pointer on this position will result in the airplane flying to the station although the ground track may be slightly curved due to a crosswind. This "homing" procedure is also explained in the chapter on Cross-Country Flying.
It should be remembered that the use of radio navigation aids when in unfavorable weather conditions requires additional division of attention while attempting to maintain control of the airplane. The pilot's main concern, of course, must be airplane control.