Textron Aviation As 21 (AS21)
ICAO AS21 Light

Textron Aviation As 21

Twin Jet

The Aero L-29 Delfín is a Cold War-era jet trainer that became the most widely produced jet training aircraft in history, with over 3,600 built between 1963 and 1974. Designed by Czechoslovakia's Aero Vodochody, the L-29 was selected as the standard jet trainer for the entire Warsaw Pact, serving air forces from East Germany to Egypt. Its rugged construction, docile handling, and simple maintenance made it ideal for ab-initio jet training, introducing thousands of pilots to jet operations during the height of the Cold War. The straight-wing design and side-by-side seating were unconventional for a jet trainer but contributed to its forgiving flight characteristics and excellent instructor-student communication. Powered by a single Motorlet M-701 turbojet producing 1,960 pounds of thrust, the Delfín cruises at around 340 knots and can reach altitudes above 36,000 feet, though typical training missions operated much lower. After the fall of the Iron Curtain, hundreds of surplus L-29s entered the civilian market, where they found new life as affordable warbird aircraft for aerobatic displays, formation flying, and jet transition training. Today the type remains popular in North America with warbird collectors and flight schools offering jet upset training, prized for its relatively low operating costs compared to Western jet trainers and its honest, predictable handling that forgives student errors while still delivering an authentic jet experience. SkyMeter has tracked 114 flights across 13 airframes and 9 operators, with SOSA GLIDING CLUB the largest observed operator.

✈
ACTIVE AIRFRAMES
13
last 7 days
🏢
OPERATORS
9
unique airlines
📊
FLIGHTS
114
tracked
⏱
AVG DURATION
28m
per flight
⚠
INCIDENT RATE
2.6%
3 flagged
ⓘ

Safety in context

The incident rate counts flights with ANY safety event detected by SkyMeter: go-arounds (a routine response, not a failure), unstable-approach gate flags (advisory thresholds), rejected takeoffs (the system working as designed), and runway events. It is NOT an accident rate or fatality rate. For accident statistics, refer to the NTSB Aviation Accident Database (USA) or the Aviation Safety Network. See methodology for what each event type measures.

Performance

Speed envelope & approach

Vref
80 kt
Vref range
—
Vmo
—
Mmo
—
Vne
250 kt
Vs1 (clean)
63 kt
Vs0 (landing)
58 kt
Vfe
140 kt
Approach category
—

Dimensions

Airframe geometry

Wingspan
—
Length
—
Tail height
—
Wheelbase
—
Gear width
—
Wake category
L

Weight & identification

Operating limits

MTOW
6,000 lb
MALW
—
Manufacturer model
AS 21
FAA designator
—
Registered
—

Recent incidents

Flagged flights of AS21

20
10/10/2026
23m
△ Low approach-stability score
10/9/2026
24m
△ Low approach-stability score
10/9/2026
2h 26m
△ Low approach-stability score
9/27/2026
1h 16m
△ Low approach-stability score
9/26/2026
5h 3m
△ Low approach-stability score
9/26/2026
35m
△ Low approach-stability score
9/21/2026
1h 19m
△ Low approach-stability score
9/19/2026
27m
△ Low approach-stability score
9/19/2026
34m
△ Low approach-stability score
9/13/2026
40m
△ Low approach-stability score

Recent flights

Real flights of AS21 · airborne ≥ 20 min

30
10/11/2026
49m
No alerts
10/11/2026
1h 17m
No alerts
10/11/2026
27m
No alerts
10/11/2026
25m
No alerts
10/10/2026
46m
No alerts
10/10/2026
1h 1m
No alerts
10/10/2026
25m
No alerts
10/10/2026
47m
No alerts
10/10/2026
31m
No alerts
10/10/2026
20m
No alerts
10/10/2026
33m
No alerts
10/10/2026
20m
No alerts
10/10/2026
26m
No alerts
10/10/2026
34m
No alerts
10/10/2026
42m
No alerts
10/10/2026
23m
△ Low approach-stability score
10/10/2026
51m
No alerts
10/10/2026
24m
No alerts
10/9/2026
59m
No alerts
10/9/2026
23m
No alerts
10/9/2026
1h 7m
No alerts
10/9/2026
1h 41m
No alerts
10/9/2026
44m
No alerts
10/9/2026
7h 17m
No alerts
10/9/2026
24m
△ Low approach-stability score
10/9/2026
43m
No alerts
10/9/2026
2h 26m
△ Low approach-stability score
10/8/2026
3h 32m
No alerts
10/8/2026
29m
No alerts
PRO
You're seeing the last 7 days
Pro unlocks the full 90-day window for stats, operators, recent flights & incidents.
Upgrade to Pro
© SkyMeter · All flight data subject to ODbL attribution · Tracking window: 7 days (free tier)