Nop ! It's not that. The principal reason is too much weight, too much fuel used.
Elbit Hermes 900
General characteristics
Crew: 2 on ground
Capacity: 350 kg (770 lb) useful payload
Length: 8.3 m (27 ft 3 in)
Wingspan: 15 m (49 ft 3 in)
Gross weight: 1,100 kg (2,425 lb)
Powerplant: 1 × Rotax 914, 86kW (115HP)
[Weight (Installed) : 75.5 Kg (166.4 lbs)]
Performance
Maximum speed: 220 km/h (137 mph; 119 kn)
Cruising speed: 112 km/h (70 mph; 60 kn)
Endurance: 36 hours
Service ceiling: 9,144 m (30,000 ft)
TAI Anka
General characteristics
Crew: none
Capacity: 200 kg useful payload
Length: 8 m (26.2 ft)
Wingspan: 17.3 m (56.7 ft)
Max. takeoff weight: 1,600 kg (3,527 lb)
Powerplant: 1 × Thielert Centurion 2.0 turbocharged four-cylinder engine, 114 KW (155 hp)
[Weight (incl. all accessories): 149,8 kg (330.5 lbs)]
Performance
Maximum speed: 217 km/h (135 mph; 117kn)
Cruise speed: 204 km/h (126 mph; 110 kn )
Endurance: 24 hours
Service ceiling: 9,144 m (30,000 ft)
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