USDA FOREST SERVICE FEPP, CALIFORNIA DEPT OF FORESTRY AND FIRE P· ICAO24 a5324b· last seen 6d ago

N434DF is a Marsh Aviation S-2F/S-2T Turbo Tracker, a twin-engine turboprop operated by USDA FOREST SERVICE FEPP, CALIFORNIA DEPT OF FORESTRY AND FIRE P. SkyMeter has tracked 368 flights totalling 296 hours of airtime via ADS-B across 3 callsigns. The most frequent segment is KMCC to KMCC. Service window in our records spans 508 days. Of those flights, 42 (11.4%) carry at least one detected incident: a go-around, unstable approach, stall warning, or runway excursion. The Marsh Aviation S-2F/S-2T Turbo Tracker has a maximum takeoff weight of 28,500 lb, medium wake category.

About the Marsh Aviation S-2F/S-2T Turbo Tracker

The S-2T Turbo Tracker represents one of aviation's most successful second lives: a Cold War submarine hunter reborn as a frontline firefighting airtanker. Originally designed by Grumman as the carrier-based S-2 Tracker for the U.S. Navy in the 1950s, these twin-engine aircraft patrolled the seas hunting Soviet submarines until retirement in the 1970s. Marsh Aviation of Arizona then pioneered a radical conversion in the 1980s, replacing the original piston engines with Garrett TPE331 turboprops and adding a 1,200-gallon retardant tank where sonobuoys and torpedoes once lived. The transformation created an airtanker purpose-built for the low-altitude, high-heat environment of wildfire suppression.

The S-2T's naval DNA makes it uniquely suited to firefighting. Its rugged airframe was engineered for carrier landings and low-level maritime patrol, giving it exceptional strength and maneuverability at the altitudes where airtankers work. The turboprop engines deliver reliable power in hot, high conditions where piston engines struggle, and the aircraft's relatively compact size allows it to operate from shorter airstrips near remote fire zones. With a cruise speed around 180 knots and the ability to make multiple drops per sortie, the S-2T became a workhorse for state and federal agencies across the American West. California Department of Forestry and Fire Protection (CAL FIRE) operates the largest fleet, with aircraft based at air attack bases throughout the state.

While newer purpose-built airtankers have entered service, the S-2T remains valued for its proven reliability and lower operating costs compared to jets. The type typically operates at weights up to 28,500 pounds, with approach speeds around 95 knots allowing precise drops in confined terrain. Most examples flying today are ex-Navy airframes from the 1950s and 1960s, now logging their sixth or seventh decade of service in a mission their designers never imagined. SkyMeter has tracked flights across airframes and operators, with the largest observed operator.

✈
FLIGHTS
368
all time
⏱
FLOWN HOURS
296
tracked time
📍
AIRPORTS VISITED
41
unique
📡
CALLSIGNS
3
71 routes
📅
SERVICE PERIOD
5/29/2025 → 10/19/2026
first → last
⚠
INCIDENT RATE
11.4%
42 flagged

Top routes

By flight count

10
21
14
9
8
5
4
KMCC → E36
4
3
KSTS → O31
2
2

Flight numbers

Most-flown by this airframe

3

Aircraft specifications

Marsh Aviation S-2F/S-2T Turbo Tracker

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

Recent flights

Newest 50 operations of N434DF

50
10/19/2026
53m
No alerts
10/19/2026
1h 25m
No alerts
10/18/2026
37m
No alerts
10/18/2026
22m
No alerts
10/15/2026
45m
No alerts
10/12/2026
1h 0m
No alerts
10/10/2026
5m
No alerts
10/7/2026
22m
No alerts
9/29/2026
15m
No alerts
9/26/2026
1h 3m
No alerts
9/22/2026
9m
No alerts
9/14/2026
5m
No alerts
9/11/2026
41m
No alerts
9/11/2026
5m
No alerts
8/29/2026
15m
No alerts
8/28/2026
36m
No alerts
8/28/2026
6m
No alerts
8/20/2026
5m
No alerts
8/12/2026
6m
No alerts
8/12/2026
30m
No alerts
8/9/2026
21m
No alerts
8/8/2026
12m
No alerts
8/5/2026
8m
No alerts
8/2/2026
7m
No alerts
8/2/2026
6m
No alerts
8/2/2026
34m
No alerts
7/31/2026
2h 41m
No alerts
7/30/2026
2h 20m
No alerts
7/28/2026
48m
No alerts
7/27/2026
27m
No alerts
7/27/2026
40m
No alerts
7/21/2026
33m
No alerts
7/21/2026
1h 1m
No alerts
7/21/2026
1h 41m
No alerts
7/17/2026
1h 43m
No alerts
7/16/2026
14m
No alerts
7/15/2026
36m
No alerts
7/14/2026
21m
No alerts
7/13/2026
2h 9m
△ Low approach-stability score
6/29/2026
59m
No alerts
6/28/2026
37m
No alerts
6/14/2026
43m
No alerts
6/9/2026
1h 21m
No alerts
6/9/2026
30m
No alerts
6/9/2026
33m
No alerts
6/8/2026
2h 8m
No alerts
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