To offset the currently scarce battery density supersonic electric aircrafts could use assisted launch strategies to save upto 5 - 35% of battery capacity needed for takeoff and intial climb. Catapults are commonly used on aircraft carriers and are tried and tested , they could be installed in high volume airports owing to high infrastructure costs. Airship assisted launch if scaled well to could offer significant savings in the long run. 7-10% per takeoff is a massive saving. With companies like Airship Industries already building airships for cargo electric supersonic aircraft could be retrofitted to launch until high volume necessitates specially built airships.

takeoff comparison

1. Electromagnetic Catapult

  • Energy Savings: 35% (630 kJ/kg)
  • Initial Speed: 100-150 m/s
  • System Cost: $30-40M for infrastructure

Technical Requirements

  • Power substation: 15-20 MW peak
  • Track length: 200-300m
  • Acceleration: 3-4 G
  • Cooling systems
  • Control systems

Advantages

  • Highest energy savings
  • Weather independent
  • Repeatable launches
  • No onboard launch fuel/equipment
  • Precise control

Disadvantages

  • High initial infrastructure cost
  • Fixed location
  • High peak power demand
  • Complex maintenance

Operational Considerations

  • Launch cycle time: 15-20 minutes
  • Crew requirements: 3-4 technicians
  • Annual maintenance: 2-3 weeks
  • Power infrastructure needed

2. Hybrid Propulsion

  • Energy Savings: 25% (450 kJ/kg)
  • Initial Speed: 80-100 m/s
  • System Cost: $2-3M per aircraft modification

Technical Requirements

  • Fuel storage: 200-300 kg capacity
  • Dual propulsion systems
  • Modified fuel management
  • Enhanced cooling systems

Advantages

  • Flexible operations
  • No fixed infrastructure
  • Proven technology
  • Multiple launch locations

Disadvantages

  • Added weight penalty
  • System complexity
  • Fuel logistics
  • Reduced payload capacity

Operational Considerations

  • Pre-flight prep: 1-2 hours
  • Additional maintenance
  • Fuel availability needed
  • Dual certification required

3. Rocket-Assisted Take-Off (RATO)

  • Energy Savings: 20% (360 kJ/kg)
  • Initial Speed: 120-180 m/s
  • System Cost: $50-75K per launch

Technical Requirements

  • Solid rocket boosters
  • Launch attachment points
  • Jettison mechanisms
  • Safety systems

Advantages

  • Simple system
  • High thrust
  • Minimal aircraft modification
  • Location flexible

Disadvantages

  • Single-use boosters
  • High per-launch cost
  • Safety concerns
  • Recovery requirements

Operational Considerations

  • Setup time: 30-45 minutes
  • Special handling requirements
  • Hazardous materials
  • Recovery operations

4. Airship Assisted

  • Energy Savings: 7% (126 kJ/kg)
  • Initial Speed: 15-20 m/s
  • System Cost: $15-20M for airship system

Technical Requirements

  • Airship volume: 6,244 m³
  • Height capability: 25,000 ft
  • Release mechanism
  • Weather monitoring

Advantages

  • Zero-runway operations
  • Low noise
  • Environmentally friendly
  • Multiple launch locations

Disadvantages

  • Minimal energy benefit
  • Weather dependent
  • Complex operations
  • Large support team

Operational Considerations

  • Weather limitations: 70% of days
  • Setup time: 3-4 hours
  • Helium replenishment
  • Large ground crew required

5. Subsonic Climb (Baseline)

  • Energy Savings: 0% (baseline)
  • Initial Speed: 80-100 m/s
  • System Cost: No additional cost

Technical Requirements

  • Standard runway
  • Normal takeoff systems
  • Standard aircraft systems
  • Regular maintenance

Advantages

  • Simple operations
  • Proven approach
  • No special equipment
  • Flexible locations

Disadvantages

  • No energy savings
  • Full battery weight
  • Longer acceleration phase
  • Higher energy usage

Operational Considerations

  • Standard flight operations
  • Normal maintenance
  • Regular crew requirements
  • Standard facilities

Comparative Metrics

Cost per Launch (USD)

  1. Subsonic: $200-300
  2. EM Catapult: $500-700
  3. Hybrid: $1,000-1,500
  4. Airship: $3,000-4,000
  5. RATO: $50,000-75,000

Weather Dependency (% of Operable Days)

  1. EM Catapult: 95%
  2. Subsonic: 90%
  3. Hybrid: 90%
  4. RATO: 85%
  5. Airship: 30%

Setup Time

  1. Subsonic: 30 min
  2. EM Catapult: 15 min
  3. Hybrid: 90 min
  4. RATO: 45 min
  5. Airship: 240 min

Infrastructure Requirements (1-10 scale)

  1. Subsonic: 3
  2. RATO: 4
  3. Hybrid: 5
  4. EM Catapult: 8
  5. Airship: 9

Maintenance Complexity (1-10 scale)

  1. Subsonic: 3
  2. RATO: 4
  3. Hybrid: 7
  4. EM Catapult: 8
  5. Airship: 9

Technical Risk (1-10 scale)

  1. Subsonic: 2
  2. Hybrid: 4
  3. RATO: 6
  4. EM Catapult: 7
  5. Airship: 9

Except for first paragraph commentary ,text and graph from claude.