USA 81 (21949)

COSPAR: 1992-023A | Alt Name: USA 81

Image

Additional Sources

Launch Details

Launch Date

April 25, 1992

Launch Site

AFWTR

Launch Pad

SLC4W

Launch Vehicle

Titan II SLV

Orbital Elements

NORAD ID

21949

International Designator

1992-023A

Epoch

Sat, 04 Jul 2026 02:38:39 GMT

Apogee

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Perigee

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Inclination

85.01°

Right Ascension

64.24°

Eccentricity

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Argument of Perigee

70.39°

Period

100.53 min

Mean Motion

14.32 rev/day

Latitude

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Longitude

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Altitude

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Velocity

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Polar Plot

3D Visualization

Basic Satellite Info

Name

USA 81

Alternative Name

USA 81

Type

Payload

Status

Unknown

Owner

NRO

Country

United States

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs

1 21949U 92023A   26185.11018099  .00000187  00000-0  61985-4 0  9991

2 21949  85.0061  64.2394 0002418  70.3911 289.7542 14.32402762111451

Source: Celestrak

Summary

USA 81, also known by its OBJECT_ID 1992-023A, is a US satellite launched on April 25, 1992, from AFWTR SLC4W using the Titan II SLV launch vehicle. It has a BUS type of NRO-T2 and utilizes a mod. P-11 bus / C-BUS configuration. The satellite measures 0.5 meters in length with a diameter of 1 meter and a span of 10 meters, indicating potential solar arrays or antenna deployment. At launch, it had a mass of 1450 kg and a dry mass of 1200 kg. It is operated by the NRO for ELINT (Electronic Intelligence) and SIGINT (Signals Intelligence) purposes with its payload designated as P-11 No. 5105. Power is provided by solar arrays and batteries, and it has a cylindrical shape augmented by antennas (Cyl + Ant).

Physical Characteristics

Length

0.5

Diameter

Span

Dry Mass

1200

Launch Mass

1450

Shape

Cyl + Ant

Radar Cross Section

Unknown

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

P-11 No. 5105

Purpose

ELINT, SIGINT

Mission

ELINT, SIGINT

Manufacturer

LMSC

Life Expectancy

Unknown

Bus

NRO-T2

Configuration

mod. P-11 bus / C-BUS

Motor

Equipment

Unknown

Power System

Solar arrays, batteries

ADCS

Unknown

Transmitter Frequency

Unknown

Map

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