Model GP5-A1

WATTS MODEL GP5-A1

DIRECTIONAL IMAGE GLIDE PATH ANTENNA

This model provides smaller critical areas for Category I/II/III Instrument Landing Systems.  Watts has recognized that worldwide engineering practices employed to overcome difficult site problems with image glide path (GP) antenna systems indicate that the antenna lateral radiation pattern is being substantially challenged in the modern airport environment.  Introduction of larger aircraft such as the Airbus A380 and airport efficiency constraints are also driving a reduction in the size of the critical area of the Glide Path system in order to take advantage of the larger jets and to increase airport capacity.

The Model GP5-A1 Antenna element, nomenclature GP5-A1, has been designed and manufactured by Watts Antenna Company to provide highly accurate guidance information to an approaching aircraft while permitting increased flow of aircraft traffic in the vicinity of the GP tower.  The development was undertaken by the manufacturer starting in the fourth quarter of 2003.

  • Directive, narrow beam produces optimum pattern in airport multipath environments.
  • Asymmetric radiation pattern provides greater use of all taxiways in the vicinity of the GP mast.
  • Rejects sources of both static and dynamic multipath on the side of the runway containing the tower. 
  • No shim adjustment necessary.
 

CATEGORY I/II/III INSTRUMENT LANDING SYSTEM
WITH SMALLER CRITICAL AND SENSITIVE AREAS

MODEL GP5-A1
DIRECTIONAL IMAGE GLIDE PATH ANTENNA

ANOTHER TOUGH SITE SOLUTION BY:
WATTS ANTENNA COMPANY
70 North Plains Road – Suite H
The Plains, Ohio 45780-1156
USA – Manufacturing Facility
Phone: +1.740.797.9380; Fax: +1.740.797.9787
WWW.WATTSANTENNA.COM
EMAIL: INFO@WATTSANTENNA.COM

 
 

THE GP5-A1 IS THE ANSWER TO SMALLER CRITICAL AND
SENSITIVE AREAS AND GREATER AIRPORT CAPACITY

Critical Area Tests Conducted in Zurich Switzerland with
a 747 Aircraft Watts GP5-A1 Image Glide Slope Antenna
Element in an M-Array

Lateral Radiation Pattern Comparison of the FA-8976 (red), Kathrein (black)
and the Watts GP5-A1 (green) Image Glide Slope Antenna Element

 
 

THE PROOF IS IN THE CRITICAL AREA COMPUTATIONS

M-Array Tower Modeled at 400 feet Offset from Runway Centerline with FA-8976
Elements Simulated 747 Aircraft Parallel to the Runway with Tail Towards the
Tower (CAT III Tolerances)

M-Array Tower Modeled at 400 feet Offset from Runway Centerline
with Kathrein Elements Simulated 747 Aircraft Parallel to the Runway
with Tail Towards the Tower (CAT III Tolerances)

M-Array Tower Modeled at 400 feet Offset from Runway Centerline with
Watts GP5-A1 Elements Simulated 747 Aircraft Parallel to the Runway with
Tail Towards the Tower (CAT III Tolerances)

 
 

SPECIFICATIONS

Nomenclature Image Glide Path Antenna Element Model GP5-A1
Frequency Range 329.0 to 335 MHz
Antenna Type 5 Collinear dipoles
Color International Orange and White
Coating Isophobic
Maximum Power 15 Watts
Reflector Type 90-Degree Trough and Corner
Pattern Type Asymmetric
Beam Displacement 5 Degrees
-3 dB Beamwidth 23 Degrees
Sidelobe Suppression 16 dB Nominal
Front-to-Back Ratio -20 dB
Input Impedance 50 Ohms Nominal
VSWR < 2.0 to 1
Monitor Impedance 50 Ohms Nominal
Monitor Coupling 12 dB Nominal
Radome Type Full Cover – Fiberglass
Length 2.74 Meters (108 Inches)
Height 79 CM (31 Inches)
Weight 22.68 KG Approximate (50 lbs)
Heaters Optional
 

GP5-A1 Downloadable Hi-Resolution Brochure

Watts 2017 Product Brochure