P-11 No. 4428

Re-entered 22 Feb 1980

P-11 No. 4428 (NORAD 7247, COSPAR 1974-020C) was a US satellite that re-entered Earth's atmosphere on 22 Feb 1980, launched on 10 Apr 1974 on the HEXAGON SV-8 mission. It was operated by NRO / SAFSP as part of the EHH B programme. The spacecraft was built by LMSC/ESYS on the P-11 H bus, with a mass of 162 kg. Like most satellites in low orbits, it was gradually slowed by atmospheric drag until re-entry. Historical record from Orbital Radar's satellite archive, cross-referenced with the live satellite catalogue.

1974

launched

1980

re-entered

years on orbit

162

kg mass

Lifecycle

Launched10 Apr 1974 · on the HEXAGON SV-8 mission

Operational22 Feb 1980 · entered service

Retired22 Feb 1980 · end of operational service

Re-entered22 Feb 1980 · atmospheric re-entry — object destroyed

Specifications

NORAD ID7247

COSPAR1974-020C

TypeSatellite

OperatorNRO / SAFSP

Country / StateUS

ManufacturerLMSC/ESYS

BusP-11 H

Mass162 kg

ProgrammeEHH B

CategorySIG

OrbitLEO (LLEO/P)

Altitude501 × 528 km

Inclination94.0°

Frequently asked questions

What happened to P-11 No. 4428?

P-11 No. 4428 re-entered Earth's atmosphere on 22 Feb 1980, ending a mission that began with its launch in 1974. Objects in low orbits are gradually slowed by atmospheric drag until they fall back and burn up on re-entry.

When did P-11 No. 4428 re-enter the atmosphere?

P-11 No. 4428 re-entered on 22 Feb 1980, according to Orbital Radar's historical catalogue records.

Who operated and built P-11 No. 4428?

P-11 No. 4428 was operated by NRO / SAFSP and built by LMSC/ESYS (US).

Launched together

HEXAGON SV-8Re-entered 1974

Historical record from the Orbital Radar satellite archive. Sources & methodology: data sources. Accessed 2026-09-06.

Browse the live satellite directory → Re-entered satellites archive → Launch record: HEXAGON SV-8 → What is space debris? →