Triple Spec 4 Risk Assessment Table

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Risk  Assessment  Table



Prob Impact



1 Project Management 3 3

Start of project is delayed; could increase overall project cost and extend delivery date.

Can reduce meetings and other PM charges while waiting for the delay to end (e.g., optics to be delivered). Minimize by ordering critical items early, and tracking to mgt plan. 2 3 Cost overrun

Some contingency exists; major overrun would jeopardize project; low prob since making copy of existing instruments 3 3 Schedule overrun

Lead engineer oversees parts fabrication; PI oversees I&T; PM involved on daily basis in all aspects of assembly and I&T

2 Science Team Activities 3 3 Bad weather during commissioning or SV

Wait for weather to improve. Work with CTIO on telescope schedule, to build contingency into commissioning schedule. Address performance issues by clear prioritization in the plan. Some shared risk with early users.

3 Systems Engineering 1 4

Performance does not meet expectations, e.g., too much flexure

Ensure that opto-mechanical design consistent with previous versions of TripleSpec

4. The values in the Prob and Impact columns are somewhat subjective, based on prior experience and incomplete knowledge of this project.

need to remove risk from the project)

Notes: 1. "Prob" is the probability that an event will occur, with 1 being the lowest and 5 the highest 2. "Impact" is the result of the event's occurring, and the overall effect on the project

3. Prob x Impact: 1-6 = acceptable risk (blue -- requires lead engineer oversight); 13-16 = risk to project success (red -- requires direct PI and executive oversight) 7-12 = moderate risk (yellow -- requires SE or PM oversight);


Risk  Assessment  Table

3 3 Poor throughput in some parts of spectrum

Expand wavelength range of spectrograph. Obtain spectral scans of witness samples from A/R coating for throughput models 2 3 ICD omits a critical element

Review ICD by PM, techs, other engineers before finalizing. Recover: work with various engineering groups; likely to surface at detailed design phase

2 4 ICD incorrectly describes a critical element

Review before finalizing. Early subsystem closure across interfaces. Recover: rework parts or use intervening adaptors.

2 4

ATP omits critical element, inadequate describes passing results, ambiguous test procedure, etc.

Review ATPs from other similar projects. Third party review. Recover: replan with engineer input, management approval. 2 5 Safety document omits issue

or inadequately addresses it.

Review other project safety documents. Third party review, esp. NOAO-N/S safety officers and CTIO operations staff.

4 Spectrograph Fabrication

-- Optics 1 5

Optics design or specification errors

Experienced designer uses familiar package. Modify previous working designs.

1 3 Inadequate specs sent to vendor

Compare with specs of previous instruments. Careful discussion of specs with vendors. Supply spec when discover error.

2 3 Difficulty obtaining materials

Avoid exotic materials, larger diameters and thickness in design. Consult with optics and materials vendors. Recover: identify second source for challenging elements.

3 4 Unanticipated difficulty fabricating to spec

Review design with vendor, change design to reduce risk. Understand fabricator's

capabilities, review previous work. May need to have a different vendor make part.

3 4

Optics breakage during/after fab; thermally sensitive CaF2 elements in Guider.

Identify sensivite parts in advance. Ensure only senior, experienced personnel handle sensitive optics. Use proven lens cell

designs, and ensure elements cool/warm at safe rates.


Risk  Assessment  Table

3 3 Optics delivered late due to reasons internal to vendor.

Finalize optical design as early as possible. Select vendors that have delivered on time in the past, even if they are slightly more expensive.

Review design with selected vendor to discover where small changes in the design have a large impact on manufacturability. Recover: revise I&T plan.

-- Mechanical

3 3 Design/specification errors Experienced ME uses familiar design package. Modify existing design drawings. 1 3 Inadequate specifications

supplied to vendor

Compare with previous instrument drawings. Careful discussions with vendors when send out to bid. Recover: send spec when error is discovered.

1 3 Difficulty obtaining materials. Avoid exotic materials, or unusually large size or thickness. 2 4 Unanticipated difficulty

fabricating to spec

Review design with vendor to identify fab challenges; change design to reduce these. Understand vendor capabilities, review previous work. Recover: use backup vendor.

2 4

Parts not delivered to design, or performance failure (e.g., Dewar doesn't hold vaccum)

Select vendors with good performance histories. Verify correct parts at critical points during fab at vendor site. Recover: rework.

3 3 Late delivery due to reasons internal to vendor.

Select vendors with on-time delivery history. Require vendor to provide progress tracking as part of contract. Recover: Schedule slip plus replanned I&T process.

-- Electronics & Sensors 1 2 Incorrectly specified parts, leads to purchase errors

Base procurement docs on previous design. Recover: re-purchase if not major cost item. 2 2 Wiring errors or damage

Use experienced techs to install/test. Test early in integration process. Recover: re-wiring and repair.


Risk  Assessment  Table

6 Detector System 3 3 Detectors delivered late

Ensure detectors and mux ordered early in project. PM/SE maintain close contact with vendor regarding progress. Try to obtain early delivery of ROIC.

3 5 Detector delaminates, especialy during I&T

Ensure slow cool/warm rates. Map bad pixels on every cooldown.

2 5 Controller destroys detector Use ROIC to test controller and cabling before using "flight" arrays 3 3 In-Dewar cabling delivered late. Place order early. Recover: NOAO fabs cables for test Dewar to hold schedule.

3 3

Price increase on in-Dewar cabling due to exchange rate fluctuations.

Order early. Try to negotiate price in US dollars. Hold capital contingency.

2 3 Unacceptable performance of vendor-supplied cabling.

Select known vendor. NOAO fabs cables to hold schedule.

2 3 Problems with modifications to / performance of test Dewar.

Care in specification, design, fab. Consult with experienced test eng. and tech. Place order early. Use "tiger team" to address problem.

3 5 Software makes controller hazardous to arrays

Use ROIC to test controller software before using "flight" arrays

2 4 Controllers delivered late

Order controllers very early in project. PM visits ARC when on personal trips to San Diego.

7 Software 4 4 Late delivery from remote site

Local progress monitoring by Project

Scientist, weekly reporting to PM. PS and SE alert to requirements creep. Recover:

prioritize modeules based on when needed, and assign second local person to complete work, if available.


Risk  Assessment  Table

3 4 Interfaces not adequate, useful or complete

PS and SE carefully specify funcionality. Extensive reuse of existing software. Local detector I&T beta testing. Beta test with actual TCS on Blanco 4-m. PS tests User Interface. SE site visit to Cornell during software integration.

8 Integration and Test 4 4 Detector subsystem I&T takes longer than expected

Experience-based careful and detailed I&T planning , using experienced personnel. Recover: Methodical, consultative problem solving. Draw on additional staff to complete work.

4 4 Lab I&T takes longer than expected

Experience-based careful and detailed I&T planning , using experienced personnel. Recover: Methodical, consultative problem solving. Draw on additional staff to complete work.

2 5 Key part damaged during I&T

Detailed operation plan and pre-execution training for major/critical assembly steps. Design and fab custom fixtures as

appropriate. Use experienced technical personnel. Use proper ESD procedures. Recovery: re-fab with possibly significant cost/schedule impacts.

3 4 Integrated instrument does not pass initial Pre-ship AT.

Write detailed, understood, accepted ATP early. Schedule contingency between ATP and shipping. Review points of failure and passing requirements. Recover: Develop engineering plan and schedule for fixes. Develop second-pass ATP with executive oversight.

2 4 Shipping damage.

Care in shipping vendor selection, based on past performance. Use NOAO experience with prior instruments in shipping to Chile. Review crate design. Recover: Insure if NSF permits.


Risk  Assessment  Table

2 3 Reassembly at telescope takes longer than expected.

Provide proper work space, tools, etc. on site. Assign on-site labor as appropriate. Develop disassembly and reassembly procedures and checklists early, test during disassembly for shipping.

Photographic documentation of procedures. Recover: Reschedule on-site ATP and commissioning.

2 4 Does not pass Final AT, initially.

Write detailed, understood, accepted ATP early. Schedule contingency between ATP and commissioning. Review points of failure and passing requirements.

Recover: Develop engineering plan and schedule for fixes. Develop second-pass ATP with executive oversight. Re-schedule subsequent commissioning and science runs.

9 Documentation & Training 3 3 Documentation takes longer than anticipated to generate

Begin documentation on schedule and sustain activity, despite other project

priorities. Reuse content from other projects. Use non-project staff as appropriate, e.g., HTML formatting, Web site construction and maintenance. PM oversight to keep sustained activity.

3 3

Technical documentation inadequate for operational troubleshooting, service, or repair.

Reuse format/content from other projects. Advance, experience-based identification of most likely problem areas, capture early in document development. Test with on-site support staff during Final AT and

Commissioning. Recover: Use "living document" approach, incorporating additions, changes, improvements immediately when identified. Ongoing responsibility of PS and SE in Observatory support roles.


Risk  Assessment  Table

2 5

Training inadequate, results in accident with harm to

personnel or equipment

Generate training materials on schedule, in clear and useable format. Multimedia: text, images, video, hands-on. Third party review by NOAO-N/S safety officers. Test with project staff prior to delivery, if feasible. Test with on-site support staff immediately after delivery. Immediately incorporate

improvements into training documents and procedures. PM oversees training effort.