Mission & System Cost Estimation Skill

Applicable Phases

• Primary: Phase A (ROM for proposals, mission feasibility), Phase B (refined estimates for confirmation review)
• Supporting: Phase C (cost-at-completion tracking), Phase D (actuals reconciliation)

Ownership Boundary

Cost Estimation Methodology

1. Select the Cost Model

Choose the appropriate model based on mission type and available data:

Default approach: If the user doesn't specify, use mass-based parametric CERs (USCM-class) with NewSpace adjustment factors where applicable.

2. Spacecraft Bus Cost (Hardware)

Estimate each subsystem using mass-based CERs. Generic form:

$$C_{subsystem} = a \cdot M^b \cdot F_{complexity}$$

Where:

• $M$ = subsystem mass (kg)
• $a$, $b$ = model coefficients (subsystem-specific)
• $F_{complexity}$ = complexity adjustment (1.0 = average, 0.7 = COTS/high-heritage, 1.5 = novel/custom)

Reference CER Coefficients (USCM-class, FY2020$K)

⚠️ These are reference values only. Actual CER coefficients vary by source database and should be stated with their provenance. Ask the user if they have project-specific CERs.

NewSpace Adjustment Factors

For commercial/startup missions, apply reduction factors to traditional CERs:

3. Payload / Instrument Cost

Use NICM or analogy:

• Optical instruments: $C = f(\text{aperture diameter}, \text{mass}, \text{detector type})$
• RF instruments (SAR, radiometers): $C = f(\text{antenna area}, \text{power}, \text{bandwidth})$
• In-situ (spectrometers, drills): Best estimated by analogy to heritage instruments.

Rule of thumb: Payload cost is typically 20-40% of spacecraft bus cost for observatory missions, but can exceed bus cost for flagship science instruments.

4. Wrap Factors (Non-Hardware Costs)

Hardware cost alone dramatically underestimates total mission cost. Apply wrap factors:

5. Mission Lifecycle Cost

Assemble the total:

$$C_{total} = C_{payload} + C_{bus} + C_{PM/SE/MA} + C_{I&T} + C_{launch} + C_{ground} + C_{ops} + C_{reserve}$$

Cost Reserve (Unallocated Future Expenses — UFE):

• Phase A: 30-50% of estimated cost
• Phase B: 20-30%
• Phase C/D: 10-15%
• NASA policy (NPR 7120.5): minimum 25% UFE at KDP-C for Class B missions.

6. Cost-Risk Analysis

Go beyond point estimates:

Confidence Levels

• 50th percentile (P50): Equal chance of overrun or underrun. Typical for proposals.
• 70th percentile (P70): Common for budgeting. NASA often uses P70 for Class B/C.
• 80th percentile (P80): Conservative. Used for cost caps and flagship missions.

S-Curve Generation

If uncertainty distributions are available:

1. Assign triangular or log-normal distributions to each subsystem cost (min, most likely, max).
2. Run Monte Carlo simulation (1000+ draws).
3. Plot cumulative probability vs. total cost = S-curve.
4. Read off P50, P70, P80 values.

Simplified approach (Phase A): Apply cost growth factors from historical data:

• Average NASA mission cost growth: 1.4× from Phase A to actuals
• Average commercial: 1.2× (smaller scope, fewer changes)

7. Design-to-Cost (DTC)

When the user specifies a cost cap:

1. Work backward from the cap to allocate subsystem budgets.
2. Identify which subsystems are cost-driving (typically payload, structure, and ADCS).
3. Flag if the cost cap is unrealistic given the mission requirements.
4. Recommend trades: reduce performance, increase COTS usage, descope payload, or change orbit.

Common Reference Costs (FY2025$, approximate)

For quick sanity checks and Phase A estimates:

⚠️ These are order-of-magnitude reference points. Actual costs vary enormously based on complexity, heritage, and programmatic approach. Always state the basis of estimate.

Output Format

1. Cost Estimate Report (cost_estimate.md)

A Markdown document containing:

• Basis of Estimate (BoE): Model used, key assumptions, cost year, heritage reference
• Cost Breakdown Table: By WBS element (hardware, PM, SE, I&T, launch, ground, ops)
• Subsystem Cost Table: By spacecraft subsystem
• Confidence Level: Point estimate and stated confidence (P50/P70/P80)
• Cost Drivers: Top 3 cost-driving items
• Cost-Risk Summary: Key uncertainties and their cost impact
• 🟢 / 🟡 / 🔴 Status: Green if within cap/target, yellow if within reserve, red if exceeds cap

2. Cost Comparison Table (cost_comparison.csv)

If multiple options are being compared (for trade-study-manager):

• Side-by-side cost breakdown for each option
• Lifecycle cost comparison (development + operations over mission life)

Verification & Cross-Checks

• Mass-cost correlation: Verify that $/kg is within reasonable bounds for the mission class (typically $50K-500K/kg for traditional, $10K-100K/kg for NewSpace).
• Historical analog: If possible, compare to a known mission of similar scope.
• Subsystem proportions: Check that no single subsystem exceeds 40% of bus cost unless justified (e.g., a very large solar array).

Interface

• Reads from: /requirements/, /analysis/systems-engineering-assessment/ (mass budget), /analysis/structural-assessment/ (mass properties), all domain skill outputs (for subsystem mass inputs)
• Writes to: /analysis/cost-estimation/
• Consumed by: trade-study-manager (cost as a Figure of Merit), systems-engineering-assessment (mission-level summary), project management / proposal teams