lighter-than-air vehicles - Defense Innovation Marketplace

Table 28: ISIS Technical SpecificationsDemoObjectiveLength 511 ft. 1,000 ft.Diameter 161 ft. 328 ft.Volume 5.8M cu. ft. 60M cu. ft.Mass: 35,000 lbs. 337,000 lbs.Flight ceiling(MSL)65,000 ft. 70,000 ft.Duration Up to 1 year 10 yearsCruise Speed 49 kts. 116 kts.Max Payload 2,900 lbs. 38,800 lbs.Payload Power: 181 kW (10-16 kW to radar) for Demo versionPayload Type: Integrated radar (both versions)Figure 44: ISIS illustration Showing Technical Concept 43Some technical challenges include excesssystem mass, assembly integration of radarstructure into the airship envelope, the X-band beam forming metrology and calibration,regenerative power systemreliability, and manufacturing readiness. 42Currently, ISIS is in its third phase ofdevelopment, which started in 2009. Thisphase includes manufacturing a half-scaledemonstration system— a working model ofISIS with a half-scale envelope size andone-tenth-scale radar size. Keyaccomplishments to date include havingconducted a critical design review of thedemonstration system, an operationalmodeling and simulation experiment of theradar system, and development anddemonstration of flight dynamic controls ina lab environment. Further, the program hasdemonstrated large-scale manufacturingprototypes, completed initial integration andperformed radar power system criticaldesign reviews. The demonstration launch isplanned for February 2014, when DARPAwill conduct a 90-day flight program beforeturning it over to the Air Force while still inthe air. 44DARPA provided initial funding for ISIS inFY04. In FY10, the Air Force begancontributing funds under a joint DARPA/AirForce initiative. In September 2011, the contractwas modified to include an “on-orbit”incentive clause tied to technicalperformance, cost, and schedule.49