Attachment_1_-_Statement_of_Work.pdf

Statement of Work

Integration, Deployment, and Automation Support Agreement for the Meter Class Autonomous Telescope (MCAT) deployment to Ascension Island Auxiliary Airfield (AAF)

This SOW governs the process by which the vendor(s) will provide (a) stripping a protected aluminum coating on a 1.3m Zerodur® mirror, and (b) recoating the mirror with an equivalent coating optimized for the 360nm-1µm spectral bandpass,.

The 1.3-m NASA MCAT Telescope is located on Ascension Island.

1.0 TASK

MCAT 1.3-m mirror recoating.

1.1 Background

The Orbital Debris Program Office (ODPO) at NASA Johnson Space Center (NASA- JSC) has been granted approval by Air Force Space Command (AFSPC A8I) to deploy MCAT to Ascension Island Auxiliary Airfield (AAF) in the US Air Force (USAF) Eastern Test Range headquartered at the 45th Space Wing stationed at Patrick Air Force Base (AFB), Florida.

MCAT is a 1.3m optical telescope conceived, designed, and constructed by NASA- JSC and the Air Force Research Laboratory (AFRL) Detachment 15, Maui, HI.

MCAT’s purpose is to characterize the space orbital object environment in support of safety of flight.

The protected aluminum coating currently on the 1.3m Zerodur® mirror is degrading and must be stripped and recoated with a new protected/enhanced aluminum coating (or equivalent). If, after the existing coating has been removed, a determination is made that the mirror will require grinding/polishing services in order to return the mirror to its original condition, the Contracting Officer will coordinate these efforts in a separate purchase order.

Specifications of the Mirror Clear Aperture 1.308m (51.5”) Thickness 15.2 cm (6”) Central Hole Diameter

46cm (18.0”)

Conic Constant -1.637 F-Ratio F2.331 Radius of Curvature -6035.05 +/- 6.035 Weight Approximately 800-850 lbs.

Spectral Bandpass 360nm – 1 um

RMS WFE

(nominal)

42nm

The scope of work includes:

(1) Stripping the current protected aluminum coating, and possibly analyzing the degraded coating.

(2) Recoating the mirror with an equivalent (or better) coating, including witness samples and the necessary fixtures to hold the mirror during the coating process.

1.2 Coating Objectives

Ascension Island is a highly corrosive sea-level, marine environment with 60-90% average humidity. The island is an extinct volcanic with sulfur-rich volcanic dust.

Thus, the reflective coating requires a protective overcoat appropriate for a highly corrosive environment.

Tolerance of surface loss due to etching on the cleaned Zerodur® glass is TBD, (expected roughly 10%). Above this, polishing (and possibly grinding) will be required, which will be coordinated by NASA through a separate contract.

The contractor shall (1) strip the current coating and (2) recoat the mirror with a commercial grade coating to meet the following minimum requirements. MIL- SPECS and ISO specs upon which the requirements are based are noted and intended to provide additional clarification for the vendor.

1.2.1 Coating Requirements

1. Reflectivity optimized for 360nm-1µm spectral bandpass, e.g. protected aluminum or equivalent (such as dielectric only layers): MIL-PRF-13830B, section B.3.4 per requirements:

A. Minimum 90% average reflectivity across the above bandpass

B. Minimum 90% average reflectivity across SDSS g’r’I’z bandpasses.

(see

C. Minimum 90% must be met from the central hole of the mirror to within 5% of the outer edges of the mirror

2. Thickness of coating

A. Reflective layer (e.g., aluminum undercoat) shall be 1000 Å +/- 10%

3. Coating Edge

A. Coating should cover the glass within 5 mm of the edge of the clear aperture.

4. Protective Topcoat

A. Protective topcoat(s) must withstand the highly corrosive environment:

The front surface aluminum film shall be protected by a uniform, high quality protective topcoat which should be free from holes, foreign matter and perceptible variations in density. (MIL-PRF-13830B, section B.3.3.2 Protective film). A field SEM may be used to assess top coat uniformity and completeness.

Adhesion test shall be done on the MCAT mirror.

All other tests are anticipated for witness samples that are coated concurrently with the MCAT mirror, and subject to agreement between NASA and the vendor.

Topcoat meets the following Specifications:

B. Adhesion: ISO-9211-4: Test 6.2.1

i. tape test: #800 Magic tape, 90 degree,

1. See ISO-211-4: 6.2.1 Test Conditions for further details

2. See ISO-211-4: 6.3, Table 2 for slow pull specs: ~2-3s per 25mm

C. Abrasion: ISO-9211-4, moderate abrasion test 5.2.2

i. The coated optical surface shall show no signs of deterioration such as streaks or scratches when abraded with 50 strokes of cheesecloth applying 5N ± 1N of force.

D. Physical: ISO-211-4, section 8.5 Evaluation

i. Shall show no signs of flaking, peeling, cracking, or blistering.

E. Cosmetic: ISO-211-4, section 8.5 Evaluation

i. Shall be free of stains, smears, discolorations, streaks, hazy/cloudiness

F. Environmental and Physical Durability

Subsequent to these tests/exposures, the coated optical surface shall meet the 4.A.i Physical and 4.A.ii Cosmetic requirements above for all durability tests.

See ISO-9211-4: 8.4 Recovery: After tests, mirror shall be gently cleaned with soft clean optical cloth not warmer than 38C.

i. Cleaning Durability MIL-C-48497A

1. After immersion in acetone and ethyl alcohol and wiping with optical cotton or an appropriate clean, soft optical-grade cloth, the coated optical surface shall show no evidence of coating removal or scratches.

2. And/or cleaning with a mild detergent (proposed by vendor) + water shall leave no evidence of coating removal or scratches.

ii. Humidity Test

1. 90-95% relative humidity @50C for 24 hours

iii. Optical Durability - Solubility Tests

1. Water Solubility (ISO-9211-4)

a. Immersion in distilled water, see ISO-9211-4: 8.2 Test Conditions for further details

b. 24-hour exposure time, 1 cycle, 23± 2C

ISO-9211-4: 8.3 Table 4 degree of severity #02

2. Salt Solubility (ISO-9211-4)

a. Immersion in a saline solution, pH = 6.5-7.2 See ISO- 9211-4: 8.2 Test Conditions for further details

b. NaCl dissolved in distilled or deionized water at room temperature to obtain a concentration of 45 g/l. NaCl shall not contain >1% impurities in total

c. 24h exposure time, 1 cycle, 23± 2C

ISO-9211-4: 8.3 Table 4, degree of severity #05

iv. 24-Hour Salt-fog Corrosion Test (MIL-STD-810G_CHG-1.pdf, Method 509.6)

See ISO-9211-4: 8.4; for corrosion (vs. test E.iii.2 for solubility)

1. Recommended 35± 2C

2. 2 cycles x (24-hour exposure, 24-hour dry);

Or 1 cycle 48-hour wet, 48-hour dry

3. A 5 ± 1% by weight NaCl salt solution concentrate (section

2.2.1 and p. 260: 4.5.1.1.b)

a. <0.1% Sodium Iodide

b. <0.5% total impurities

c. no anti-caking agents

v. Acid Corrosion Test (ISO 9022-12-1 Chemical Durability Environmental test; or MilStd810G, Method 518.2)

1. 23 ± 2C

2. 6-hour exposure, 18-hour storage prior to cleaning

3. Sulfuric Acid: 2.5% H2SO4/sulfuric acid

a. OR 11.9mg (6 µl) sulfuric acid (95-90%) per 4 L of distilled or deionized water (MilStd810G, Method 518.2, p.659)

b. OR hydrogen sulfide (pH 6.9);

vi. Alkaline Corrosion Test (ISO 9022-12-2, ISO 10629: Chemical Durability Environmental test: 24-hour, 50C)

1. 23 ± 2C

2. 6-hour exposure, 18-hour storage prior to cleaning

3. Sodium hydroxide, c=0.01 mol/L, pH=12; (ISO 10629, 1996)

a. Or Potassium hydroxide (pH 11.95)

5. Coating removal

The current coating to be removed is a Magnabrite® protected aluminum.

A. Non-dielectric coats (reflective and protective overcoat, e.g. protected Al) shall be chemically strippable without damaging the underlying Zerodur® mirror.

B. Dielectric coating removal options (e.g. chemically dissolving versus removal via polishing) will be defined by the vendor and accepted by the Contracting Officer prior coating the mirror.

6. Tests and Inspection for Optical Quality (MIL-PRF-13830B)

Including 4.2.2 Surface Quality Inspection Methods No.1 and 2 for both the reflective and topcoat(s) layers (Backlit and forward lit inspections)

A. Method 1: The element to be inspected shall be viewed against a ground glass or opal surface illuminated from behind by a 40 watt incandescent or 15 watt cool white fluorescent lamp approximately 3 inches from the glass. Two or more opaque horizontal bars occupying approximately 1/2 the area of the glass shall be placed in front of and in contact with the glass.

B. Method 2: The light through ground glass from a 40 watt incandescent or 15 watt cool white fluorescent lamp shall be passed through the element. Defects are observed by light scattered from the surface while viewing it at approximately 90 degrees to the path of the beam against a dark background.

7. Tests and Inspection of Existing Coating

A. Test stripping techniques of the old coating prior to the mirror’s arrival. NASA will provide pristine witness samples of the current coating for this purpose.

B. Provide an analysis of the pristine witness samples of the original coating of the mirror to assess completeness of the original protective overcoat. NASA will provide pristine witness samples of the current coating for this purpose.

C. Provide an analysis of degraded original coating of the mirror to assess potential causes of rapid degradation.

8. Required Fixtures/Tooling used to Fasten Mirror

Note: Tooling fabricated for the original coating will be shipped with the mirror to aid in removal of the existing coating while new tooling is fabricated. This allows for the underlying surface to be assessed for any potential etching.

A. If required, design new tooling/fixtures appropriate for handling the mirror for the new coating

B. Fabricate a mass model to test the fixture

C. If required, fabricate the newly designed tooling/fixtures. Please include pricing/schedule options for each:

i. Fixture to be held with straps

ii. Trunnion/cart plus fixture

9. Witness Samples

A. Number of witness samples coated concurrently with the MCAT mirror that are needed to efficiently test the conditions above will be agreed upon with the vendor prior to the mirror coating.

B. At least 2 additional witness samples (1 coated inside the mirror annulus, 1 exterior) will remain pristine (untested).

1.2.2 Coating Deliverables

1. NASA representatives shall be allowed to:

a. Visit the vendor site to analyze the corroded mirror coating to determine how/what caused the corrosion for future mitigation purposes

b. Inspect the final coated mirror

2. Analysis of the telescope’s current coating may include:

a. Pristine witness samples provided by NASA that were coated when the mirror was originally coated, and

b. Analysis of the corroded coating on the primary mirror at time of delivery to the coating vendor.

3. Analysis of the surface (etching) of the bare Zerodur® mirror

a. After removal of old protected aluminum coating, determine whether polishing (and/or grinding) is necessary as preparation for the new coating (See section 1.3.1 for tolerance).

4. Approval by NASA of the coating design will include:

a. Ensuring coatings meet the agreed upon reflectivity requirements, balanced with protection by the overcoat

b. Coatings should be strippable without damaging the mirror

5. Quality Management Plan for the chamber and the process by which the coating will be produced by the chamber.

6. Quality Control Certification Report of the final coating on the mirror showing that the coating meets all requirements in section 1.3.1, including, but not limited to:

a. Physical

i. Blemishes

ii. Verification of coating thickness

iii. Edge coating requirement

b. Reflectivity

i. Spatially: verify across the full bandpass from the inner to outer annulus of the mirror

ii. Spectrally: plots of reflectivity as a function of wavelength

c. Results of tests performed

i. Please complete Attachment 2 of the RFQ

7. Tooling/Fixtures

a. If needed to replace existing fixtures that will be shipped with the mirror, fixtures that will be used to hold the primary mirror during the recoating process

b. If agreed upon, trunnion or cart custom made for this project

8. Witness Samples

a. Minimum of 8 Zerodur® glass witness samples will be coated simultaneously with the primary mirror: a minimum of 4 interior and 4 exterior to the mirror at regular spacing, or the number agreed to that allows efficient testing of the coating plus one set of pristine witness samples

9. Coated Mirror

a. Coated mirror with protected, enhanced Aluminum coating or equivalent to meet objectives above in section 1.3.

2.0 Place of Performance

NASA will coordinate and fund the transportation of the mirror to and from the vendor’s facility where all coating services will be performed.

3.0 Period of Performance

Period of Performance shall be convene over 120 days (or less) unless the Contracting Officer authorizes an extension via the issuance of a unilateral modification to the purchase order.

4.0 Acceptance of Deliverables

All deliverables will be considered accepted upon official notice from the Contracting Officer.

5.0 Expertise Requirements

Coating manufacturer shall demonstrate past experience and performance in meeting MIL-specs defined in section 1.3 for professional grade observatories.

Coating manufacturer shall demonstrate past experience and performance in developing/applying protective overcoats appropriate for highly corrosive environments.

6.0 Contracting Officer’s Technical Representative (COTR)

The COR/COTR is designated by the Contracting Officer to perform technical liaison between the contractor’s management and the Contracting Officer in routine technical matters constituting general program direction within the scope of the contract/task order.

Under NO circumstances is the COR/COTR authorized to effect any changes in the work required under this contract/task order whatsoever, or enter into any agreement that has the effect of changing the terms and conditions of this Task Order, or that causes the Contractor to incur any costs.

In addition, the COR/COTR will NOT supervise, direct, or control contractor employees.

Notwithstanding this provision, to the extent that contractor accepts any direction that constitutes a change to his contract/task order without prior written authorization of the Contracting Officer, costs incurred in connection therewith are incurred at the sole risk of the contract, and if involved under this Task Order will be disallowed.

On all matters that pertain to the contract terms, the contractor must communicate with the Contracting Officer. Whenever, in the opinion of the contractor, the COR/COTR requests efforts beyond the terms of the contract, the contractor shall so advise the Contracting Officer. If the COR/COTR persists and there still exists a disagreement as to the proper contractual coverage, the Contracting Officer will be notified immediately, preferably in writing.

Proceeding with work without proper contractual coverage may result in nonpayment or necessitate submittal of a contract claim. The prime contractor’s management should clearly communicate this position to its employees working on this contract and to any subcontractors also providing support.