MART Vol. II MO/MP - NESA - Civil Air Patrol

Upon receiving SARSAT coordinates and registration details, the CAP AlertOfficer will notify an Incident Commander to launch a search. The success of thesearch may depend upon several factors. The simple fact that an ELT wasaboard a missing aircraft does not necessarily guarantee that electronic searchprocedures will locate it because the unit may have become inoperative or thebatteries totally discharged. Incident Commanders may attempt to maximize thesearch effort by conducting an electronic search and a general visual searchsimultaneously when weather and other circumstances permit.NOTE: Since SARSAT/COSPAS satellites no longer monitor 121.5 MHz, wemust rely on air- and ground-based monitoring (e.g., aircraft and FAA radios).CAP is still developing procedures on how it will respond to these reports, but wecan expect these searches to take longer and be more manpower-intensive forboth air and ground teams.7.2 Locating the ELT SignalThe remainder of this chapter (except for Section 7.10) deals with searchingfor a 121.5/243 MHz ELT signal. If the signals are coming from a 406 MHz ELTthe initial search area will be much smaller and so easier to find, even if youraircraft is not equipped with the Becker SAR-DF (Doppler) unit. You can easilymodify the following procedures for this case. [How to search for the 406 MHzsignal using the Becker SAR-DF is covered in Attachment 2 (Flight Guide) and atwww.becker-avionics.com (a User Manual can also be found athttp://nhwgcap.org/ops/BeckerManual.pdf]Before you can use any technique to locate an ELT, you must first be able topick it up on your radio. The route (track line) pattern (Figure 7-1) or the paralleltrack (Figure 7-2) search patterns are the most effective at this stage. The aircraftconducting an electronic search will normally begin the search at or near the lastknown position (LKP) and fly the search pattern at altitudes from 4,000 to 10,000feet above the terrain if possible. At this altitude, the aircraft can usually interceptthe ELT signal, as well as recognize or distinguish the downed aircraft. At themaximum electronic search altitude, which is much higher than 10,000 feet,chances are slim that one can recognize or distinguish a light plane crash site.Maximum track spacing should be used initially to provide a rapid sweep of theprobability area. Successive sweeps should have a track spacing one-half thesize of the initial spacing. For example, if the track spacing is 60 nautical milesduring the initial sweep of the area, then the track spacing for the second sweepof the area should be 30 nautical miles. A third sweep of the area, if needed,should have track spacing of 15 nautical miles. This method of gauging the trackspacing applies to both track line (route) and the parallel track. These proceduresmay be repeated until the missing aircraft or survivors are located, or until it ispresumed that the batteries of the ELT have been exhausted.In mountainous terrain the initial search pattern should be arranged to crossthe ridgelines at right angles, if at all possible. The search coverage of the areashould be at right angles to the first coverage tracks to compensate for blockageof the ELT signal due to the shape of the terrain.118