VOR/LOC ILS Antenna System for Mach 2+ Aircraft
108 - 118 MHz and 328 - 336MHz
SKU: 21-20-85
The 21-20-85 VOR/ILS LOCALISER AND GLIDESLOPE antenna system comprising of a pair of high-strength blades (P/N 21-20-85A and 21-20-85B) for horizontal mounting, one on each side of a vertical stabiliser, together with an external cable harness (P/N 21-80-56).
When installed, the blades act as a loop for VOR/LOC and as a forward looking dipole for GLIDESLOPE. The combined output from the 21-80-56 is connected to a diplexer (P/N 21-80-35) which divides the signal into separate VOR/LOC and GLIDESLOPE signals, both of which derive equally from each half of the antenna system.
Mechanical design of each blade comprises an internal printed circuit half loop, foamed-in-place into a high strength epoxy-glass radome fitted to an aluminum alloy base block having an integral mounting flange. Structural design ensures high side loading acceptance as required on high speed military aircraft.
- High strength lightweight fiberglass blades
 - Low drag
 - High ratio between horizontal and vertical polarization
 - Environmental Design to MIL-STD-810
 - Loop design for omnidirectional VOR/LOC pattern
 - Fully sealed for environmental integrity
 
| 21-20-85 | |
| Model # | 21-20-85 | 
| Brand | Cooper Antennas | 
| Frequency | 
			 Localiser : 108-118 MHz Glideslope : 328-336 MHz  | 
		
| Gain (typical) | 
			 Localiser : -5 dBi Glideslope : -5 dBi (Antennas only, excluding cable harness losses)  | 
		
| VSWR | 
			 Localiser : ≤ 5.0:1 Glideslope : ≤ 3.0:1  | 
		
| Impedance (nominal) | 50 Ohms | 
| Polarization | Horizontal | 
| Radiation | 
			 VOR/Localiser : Omnidirectional Glideslope : Forward looking lobe  | 
		
| Antenna RF Connector | TNC Female | 
| System comprises of | 
			 Qty 1 - 21-20-85A (Antenna) Qty 1 - 21-20-85B (Antenna) Qty 1 - 21-80-56 (Cable harness) Qty 1 - 21-80-35 (Diplexer)  | 
		
| Construction | High strength fiberglass moulding | 
| Height | 6 inches (152mm) for single antenna | 
| Weight | 1.8 lb (0.8kg) for single antenna 6 lb (2.71kg) for system | 
| Fixing Holes | 4 x Ø 0.209 inches (5.3mm) holes, counter sunk 100° Ø 0.413 inches (10.5mm) | 
Finish
- Blue Grey
 - Other finish options are available.
 - Please specify finish required when ordering.