USDA FOREST SERVICE FEPP, CALIFORNIA DEPT OF FORESTRY AND FIRE P· ICAO24 a519a8· last seen 7d ago

N428DF is a Marsh Aviation S-2T Turbo Tracker, a twin-engine turboprop operated by USDA FOREST SERVICE FEPP, CALIFORNIA DEPT OF FORESTRY AND FIRE P. SkyMeter has tracked 206 flights totalling 130 hours of airtime via ADS-B. The most frequent segment is KHMT to KHMT. Service window in our records spans 416 days. Of those flights, 20 (9.7%) carry at least one detected incident: a go-around, unstable approach, stall warning, or runway excursion. The Marsh Aviation S-2T Turbo Tracker has a maximum takeoff weight of 28,500 lb, medium wake category.

About the Marsh Aviation S-2T Turbo Tracker

The S-2T Turbo Tracker is a turboprop conversion of the Cold War-era Grumman S-2 Tracker anti-submarine aircraft, transformed into one of the most capable single-engine-out airtankers in the aerial firefighting fleet. Marsh Aviation of Mesa, Arizona developed the conversion in the 1980s, replacing the original piston radials with twin Garrett TPE331-14GR turboprops and adding a 1,200-gallon retardant tank system. The result is an aircraft that combines the rugged carrier-capable airframe of a 1950s naval design with modern turbine reliability and the ability to operate from short, high-altitude airstrips near active wildfires.

The S-2T's low-and-slow delivery profile (it can drop retardant at speeds around 130 knots just above treetop level) makes it particularly effective for initial attack on fast-moving fires in mountainous terrain. Its twin-engine configuration provides crucial safety margins when operating in the hot, high, and heavy conditions typical of Western U.S. fire seasons, and the type's excellent single-engine performance has made it a mainstay of state and federal firefighting agencies.

The California Department of Forestry and Fire Protection operates the largest fleet, with aircraft often seen working the steep canyons of the Sierra Nevada and coastal ranges. SkyMeter has tracked flights across airframes and operators, with the largest observed operator.

FLIGHTS
206
all time
FLOWN HOURS
130
tracked time
📍
AIRPORTS VISITED
32
unique
📡
CALLSIGNS
1
55 routes
📅
SERVICE PERIOD
05/27/2025 → 07/17/2026
first → last
INCIDENT RATE
9.7%
20 flagged

Top routes

By flight count

10
6
6
6
3
3
2
2
2
2
2

Flight numbers

Most-flown by this airframe

1

Aircraft specifications

Marsh Aviation S-2T Turbo Tracker

Engines
Twin Turboprop
Vref (approach)
95 kt
MTOW
28,500 lb
Wake category
M

Recent flights

Newest 50 operations of N428DF

50
07/17/2026
1h 42m
No alerts
07/17/2026
9m
No alerts
07/17/2026
25m
No alerts
07/16/2026
13m
No alerts
07/15/2026
28m
No alerts
07/13/2026
10m
No alerts
07/13/2026
43m
No alerts
07/13/2026
19m
△ Low approach-stability score
07/13/2026
58m
No alerts
07/12/2026
52m
No alerts
07/12/2026
14m
No alerts
07/12/2026
29m
No alerts
07/11/2026
1h 17m
No alerts
06/18/2026
13m
No alerts
06/16/2026
1h 11m
No alerts
06/01/2026
41m
No alerts
05/28/2026
48m
No alerts
12/02/2025
1h 23m
△ Low approach-stability score
12/02/2025
1h 12m
No alerts
12/02/2025
20m
No alerts
11/23/2025
42m
No alerts
11/11/2025
19m
No alerts
11/10/2025
11m
No alerts
11/10/2025
1h 2m
No alerts
11/09/2025
21m
No alerts
11/09/2025
8m
No alerts
11/09/2025
9m
No alerts
11/09/2025
33m
No alerts
11/08/2025
11m
No alerts
11/08/2025
48m
No alerts
11/08/2025
10m
No alerts
11/07/2025
1h 47m
No alerts
10/31/2025
30m
No alerts
10/28/2025
20m
No alerts
09/23/2025
16m
No alerts
09/20/2025
17m
No alerts
09/13/2025
12m
No alerts
09/05/2025
31m
No alerts
09/03/2025
24m
No alerts
09/03/2025
34m
No alerts
09/02/2025
1h 21m
△ Low approach-stability score
09/02/2025
1h 8m
No alerts
09/01/2025
37m
No alerts
09/01/2025
1h 6m
No alerts
09/01/2025
8m
No alerts
08/31/2025
46m
No alerts
08/31/2025
46m
No alerts
08/30/2025
1h 1m
No alerts
08/29/2025
1h 8m
No alerts
08/28/2025
21m
No alerts
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