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OTV 4 (USA 261) (40651)
COSPAR: 2015-025A | Alt Name: X-37B OTV-4
DECAYED
Image
Additional Sources
Launch Details
Launch Date
May 20, 2015
Launch Site
Launch Pad
SLC41
Launch Vehicle
Atlas V 501
Orbital Elements
NORAD ID
40651
International Designator
2015-025A
Decay Date
5/7/2017
Basic Satellite Info
Name
OTV 4 (USA 261)
Alternative Name
X-37B OTV-4
Type
Payload
Status
Decayed
Owner
AFRCO
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Summary
The OTV 4 (USA 261), also known as X-37B OTV-4, is a reusable space plane launched by AFRCO on May 20, 2015, from the Cape Canaveral Air Force Station using an Atlas V 501 launch vehicle. With dimensions of 8.8 meters in length and span and a diameter of 2.9 meters, it has a dry mass of approximately 5000 kilograms. The spacecraft is equipped with deployable solar arrays for power generation and features a half-cylinder shape with two wings. Its mission is to serve as a reusable satellite for unspecified purposes, carrying the X-37B No. 2 F2 payload. Manufacturing was handled by BOHB (Boeing), and its operational lifetime has ranged from 225 days to over 675 days in previous missions.
Physical Characteristics
Length
8.8
Diameter
2.9
Span
8.8
Dry Mass
5000
Launch Mass
5000
Shape
Half Cyl + 2 Wing
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
X-37B No. 2 F2
Purpose
Reusable satellite
Mission
Reusable satellite
Manufacturer
BOHB
Life Expectancy
270 days (nominal); 225 days (#1); 469 days (#2); 675 days (#3)
Bus
X-37
Configuration
reusable space plane
Motor
AOCS
Equipment
?
Power System
Deployable solar array, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
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