SOW GS antennas 20230118 r7.pdf

Glide Slope Antenna with Removable Dipole Channel Assembly

SOW GS antennas 01182023

STATEMENT OF WORK

FOR

Navigation, Landing, and Weather (AJW-L700)

1.0 BACKGROUND

For many decades within the NAS, the FAA has used an image type Glide slope (GS) system for vertical guidance to aircraft during landings at many sites. These antennas are mounted on triangular shaped GS towers.

Depending on system configuration, two or three antennas are used for each GS facility. The standard GS antenna is produced using many aluminum components and mechanical/soldered fastening points.

Over time and especially in harsh environments the mechanical joints can deteriorate resulting in poor performance of the antenna. Newer versions of this same type of design are produced using brass dipoles, which can be directly soldered to. This and the use of semi-rigid cable provide significant advantages in the reliability and longevity of the asset.

Category (CAT) II/III Glide Slope systems have a more stringent and critical reliability needs requiring a very low probability that the signals will cease during the critical landing phase for aircraft. For this purpose, the components used on these systems must be of the highest quality and durability. It is for these characteristics and/or requirements that this contract is presented.

2.0 SCOPE OF WORK

2.1 The scope of this contract is to provide a higher reliability and performing Glide Slope antennas to FAA sites across the National Airspace System (NAS); focusing on CAT II & III sites.

Minimum requirements for this style antenna are noted below. I t i s a n t i c i p a t e d t h a t t h e contract shall be for one (1) year plus four (4) option years to be exercised at the discretion of the government. The contract will also include dipole channel assemblies for site repairs (E&R support).

3.0 REQUIREMENTS

3.1 Enhanced Glide slope Antenna

The contractor shall furnish all labor, plant facilities, parts, supplies, materials, fixtures, equipment, tools, test equipment, technical data/expertise, and other facilities and support necessary to provide for acquisition of the antenna made up of these primary components and/or characteristics and be pre-approved units by the FAA;

3.1.1 Brass dipoles

3.1.2 Semi-rigid coax line for cabling

3.1.3 Characteristic Impedance for both Feed and Monitor ports shall be 50 Ohm.

3.1.3.1 The input voltage standing wave ratio (VSWR) of the antenna array shall not exceed 1.20 under normal test conditions with antennas fed from a 50-Ohm line.

3.1.4 Integral Pickup: Coupling

3.1.4.1 The monitor coupling between the antenna dipole inputs to the monitor probe output shall be between 8.5 dB and 10 dB when measured at the center frequency of 332 MHz. This coupling value shall be the coupling value required for all production antennas under this contract.

3.1.4.2 The maximum change in the coupling value at any one frequency in the glide slope frequency band shall not exceed the noted values across the environmental temperature range.

Coupling 0 +0.3dB / -0.1dB (excluding ice) 0 +0.8dB / -0.1dB (with icing effects)

Phasing 0 +/-5.0 degrees

3.1.4.3 With a change in the GS Frequency, there is a potential for change in the Monitor Coupling level or value. This coupling value, set in 3.1.4.1, shall not vary more than ±1.5 dB over the glide slope frequency range (329 MHz – 335 MHz).

3.1.5 All internal radio frequency (RF) connections are soldered, no mechanical connections.

3.1.6 Metals shall be corrosion resistant or shall be coated or metallurgically processed to resist corrosion; i.e. stainless steel hardware, nickel plating, silver plating, Alodine® coating, or other approved means of protection. Paint alone is not considered adequate protection.

3.1.7 Antenna heaters shall be provided.

3.1.7.1 Heaters shall operate from 240 VAC ±15%. The circuit shall be isolated as to not interfere with RF operations: VSWR, radiation patterns, or other signal characteristics.

3.1.7.2 Heaters shall be able to operate in a continuous mode in appropriate weather conditions so as not to cause damage or interfere with RF signal.

3.1.7.3 No internal thermostat shall be provided. An external thermostat (provided by FAA site) for the GS tower will control heater activation.

3.1.7.4 Heater operation shall not affect the radiation and/or monitoring characteristics of the antennas.

3.1.8 Full dipole covers shall be provided.

3.1.9 Ninety-degree reflector assembly shall be provided.

3.1.10 Dipole Channel Assembly - The antenna unit shall have the capability of removal of the dipole channel assembly in order to facilitate ease of repairs in the field and reduce shipping costs for the repairable units. The removal of this unit shall take place without the need to open the dipole channel assembly or the dipole covers. Field technicians should only need to remove the fasteners that attach the dipole channel assembly to reflector body, cable connectors, and heater plug without any other disassembly.

3.1.11 The dipole channel assembly shall have its own part number for easy identification that is stamped or painted on the unit in a permanent means; both part number and noun/description.

The Assembly shall consist of the same characteristics as noted for the antenna.

3.2 Documentation:

3.2.1 All units provided from the contractor shall have the appropriate test documentation included to show the assets meet or exceed factory testing standards as established with the FAA.

3.2.2 All documentation shall show the correct National Stock Number (NSN), Mfg. PN, and serial number (minimum) to identify each asset tested.

3.2.3 The tester or the contractor’s Quality Control Representative shall sign all documentation.

3.2.4 Documentation is to be packaged with individual assets.

3.2.5 An electronic copy of all documentation is to be provided to the Contracting Officer’s Representative (COR).

3.3 First Article Testing/Unit Inspection:

3.3.1 All proposed Glide Slope antennas must be current/approved units by the FAA. No First Article testing will be performed under this contract. If modifications are made to an asset that changes it from the FAA baseline, an inspection of the asset will be required to further determine if said asset warrants FAA recertification or baselining. If an asset is determined to have significant changes to its structure/manufacturing, and therefore requires FAA recertification for the NAS, the asset will be deemed unsuitable for this contract

3.4 Warranty

3.4.1 The contractor shall provide a warranty of at least one (1) year or the manufacturer’s standard warranty (whichever is longer) shall apply.

4.0 Packaging, Handling, Storage, and Transportation (PHS&T)

4.1 The antenna shall be provided in a crate that is reusable for multiple shipments. This crate must be approved by AJW-L600 personnel prior to use. Provide crate specifications to the Contracting Officer (CO) and COR prior to delivery for noted approval. The antenna shall be bolted to the bottom to avoid movement during shipping and have additional protection for paint, etc. as required to protect the unit. One antenna per crate.

4.2 The dipole channel assembly can be shipped by crate or high strength cardboard/foam packing methods to protect the asset from damage. The packaging shall be capable of withstanding multiple shipments to and from Oklahoma City to FAA field facilities within the NAS.

4.3 All components and equipment shall be packaged to meet American Society for Testing and Materials (ASTM) D3951-10 Standard Practice for Commercial Packaging. Performance testing of packaging will be IAW ASTM D 4169 assurance level II distribution cycle 18.

4.4 All items shall be marked IAW MIL- STD-129R “Marking for Shipment and Storage”. Bar coding is required, 2D (PDF417) is preferred; however, (39 Code) will be accepted.

4.5 The contractor shall label the packaging with the following information:

4.7.1.1 National Stock Number (NSN) – 0000-00-000-0000

4.7.1.2 Noun – GS Antenna w/ removable channel assembly

4.7.1.3 Manufacturer – xxxxxxxxx

4.7.1.4 CAGE Code – 00000

4.7.1.5 Contract Number – (As found on the contract)

4.7.1.6 Serial Number – xxxx

4.7.1.7 Gross Weight of Container

4.6 Items subject to damage by Electrostatic or Electromagnetic field forces shall be individually wrapped in material conforming to MIL-PRF-80705E(1), Type lll. ESD Intermediate and exterior containers shall be marked with the yellow and black ESD label IAW MIL-STD¬-129R, paragraphs 5.10.20 and 5.10.20.2.

4.7 The Antenna shall meet requirement 10.6, Secured Cargo Vibration, MIL-STD-810G, Method 514.6, Category 4, Procedure I, Paragraph 4.5.2, Figure 514.6C-1 (US highway Truck Vibration Exposure).

5.0 DELIVERABLES

TASK DESCRIPTION DUE

DATE

3.1 Glide Slope Antenna

with Removable Channel Assembly

NLT [contractually named date]

3.1.4.1 Baseline Coupling Value With first delivery.

3.1.10 Dipole Channel Assembly NLT [contractually named date]

3.2 Documentation With delivery of 3.1 & 3.1.10

6.0 PERIOD OF PERFORMANCE

Delivery of materials shall be in 60 days after contract award.

7.0 PLACE OF PERFORMANCE

The Contractor shall perform the work of the contract on the Contractor’s premises.