SIMPSON MICHAEL A· ICAO24 a70446· last seen Jan 2026

N551MS is a Cessna 1SP, a twin-engine jet operated by SIMPSON MICHAEL A. SkyMeter has tracked 20 flights totalling 14 hours of airtime via ADS-B. The most frequent segment is KAFW to KAFW. Service window in our records spans 219 days. Of those flights, 6 (30.0%) carry at least one detected incident: a go-around, unstable approach, stall warning, or runway excursion. The Cessna 1SP has a 47 ft wingspan, a maximum takeoff weight of 11,850 lb.

About the Cessna 1SP

The Cessna Citation I, introduced in 1972 as the Citation 500, was the production version of the revolutionary Citation prototype that launched the light business jet category. Cessna's gamble on a straight-wing, modestly-powered twin-jet designed for owner-pilots rather than corporate flight departments proved transformative. The Citation became the best-selling business jet family in history, with over 8,000 delivered across all variants. The original Citation I prioritized simplicity and economy over raw speed, cruising at 340 knots with a range of 1,300 nautical miles, making it accessible to operators transitioning from piston twins.

Powered by two Pratt & Whitney JT15D-1A turbofans producing 2,200 pounds of thrust each, the Citation I could operate from runways as short as 3,000 feet and climb directly to FL410, capabilities that opened thousands of airports to jet traffic for the first time. Its docile handling characteristics and relatively low operating costs made it a favorite of small corporations, air ambulance operators, and freight carriers. The type remained in production until 1985, with 689 built, and many still fly today in cargo, charter, and private roles.

The Citation I established design principles (high wings for cabin space, straight wings for short-field performance, and twin Williams or P&W engines in the 2,000-3,000 pound thrust class) that Cessna refined through the Citation II, Bravo, CJ series, and beyond. Its success proved that a market existed below the traditional midsize jet segment, a lesson that reshaped the entire business aviation industry. SkyMeter has tracked flights across airframes and operators, with the largest observed operator.

FLIGHTS
20
all time
FLOWN HOURS
14
tracked time
📍
AIRPORTS VISITED
8
unique
📡
CALLSIGNS
1
9 routes
📅
SERVICE PERIOD
06/02/2025 → 01/07/2026
first → last
INCIDENT RATE
30.0%
6 flagged

Top routes

By flight count

8
2
1
1
1
1
1
1
1

Flight numbers

Most-flown by this airframe

1

Aircraft specifications

Cessna 1SP

Engines
Twin Jet
Vref (approach)
107 kt
Vmo
305 kt
MTOW
11,850 lb
Wingspan
47 ft
Length
44 ft
Wake category
Light

Recent flights

Newest 10 operations of N551MS

10
01/07/2026
1h 17m
No alerts
01/07/2026
1h 6m
No alerts
07/12/2025
37m
△ Low approach-stability score
07/11/2025
45m
△ Low approach-stability score
06/23/2025
35m
△ Low approach-stability score
© SkyMeter · All flight data subject to ODbL attribution