MiG-21SMT

Mikoyan-Gurevich · Soviet Union · first flew 1971 · fighter

The MiG-21SMT (Fishbed-K) is a VVS-only variant with an exceptionally large dorsal fuel spine — the largest of any MiG-21 — intended to dramatically extend range and patrol endurance, though the spine proved to create adverse handling characteristics.

Recognition (WEFT)

W — WingsMid-mounted, delta
E — Engines1 × turbojet, fuselage-mounted
F — Fuselage15.76 m fuselage
T — TailConventional

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Spot it by:

The enormous dorsal spine — creating a pronounced hump-backed silhouette unlike any other MiG-21 — is unmistakable. When seen in profile, the spine nearly doubles the apparent fuselage depth aft of the cockpit. This is the definitive recognition feature and cannot be confused with any other MiG-21 variant.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Range had always been the MiG-21's Achilles heel, and the SMT was Mikoyan's most aggressive attempt to fix it by enlarging the dorsal spine to carry maximum additional fuel. While the increased fuel load was valuable, pilots found the large spine created pitch instability and the variant was not popular in service. Production was limited, and many were later modified to the MiG-21bis standard or had their spines reduced. It entered service around 1971.

Variants

The MiG-21SMT is unique among single-seat MiG-21s for its exaggerated dorsal spine. The subsequent MiG-21bis used a more modest spine with a new engine rather than relying on pure fuel volume. The SMT was not exported.

Where you'll see it

Limited numbers served with VVS fighter regiments in the early-to-mid 1970s. The handling issues meant many were converted to other standards relatively quickly. No export customers received the SMT, making it one of the rarer MiG-21 variants in terms of geographic spread.

Related aircraft

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