· ICAO24 485e5d· last seen 1d ago

PH-1635 is a Textron Aviation AS 21, a twin-engine jet. SkyMeter has tracked 2,064 flights totalling 479 hours of airtime via ADS-B across 2 callsigns. The most frequent segment is EDTW to EDTW. Service window in our records spans 443 days. Of those flights, 22 (1.1%) carry at least one detected incident: a go-around, unstable approach, stall warning, or runway excursion. The Textron Aviation AS 21 has a maximum takeoff weight of 6,000 lb, light wake category.

About the Textron Aviation AS 21

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 flights across airframes and operators, with the largest observed operator.

FLIGHTS
2,064
all time
FLOWN HOURS
479
tracked time
📍
AIRPORTS VISITED
8
unique
📡
CALLSIGNS
2
11 routes
📅
SERVICE PERIOD
5/30/2025 → 8/16/2026
first → last
INCIDENT RATE
1.1%
22 flagged

Top routes

By flight count

6
21
16
10
6
4
1

Flight numbers

Most-flown by this airframe

2

Aircraft specifications

Textron Aviation AS 21

Engines
Twin Jet
Vref (approach)
80 kt
MTOW
6,000 lb
Wake category
L

Recent flights

Newest 50 operations of PH-1635

50
8/16/2026
29m
No alerts
8/16/2026
11m
No alerts
8/16/2026
10m
No alerts
8/12/2026
2m
No alerts
8/12/2026
28m
No alerts
8/10/2026
19m
No alerts
8/10/2026
17m
No alerts
8/10/2026
17m
No alerts
8/10/2026
19m
No alerts
8/10/2026
16m
No alerts
8/10/2026
20m
No alerts
7/31/2026
2m
No alerts
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