The stall speed of a Cessna 172 varies depending on its configuration, with a clean stall speed (Vs1) of 57 MPH and a landing configuration stall speed (Vso) of 49 MPH.
Understanding Cessna 172 Stall Speeds
Stall speed is a critical performance parameter for any aircraft, representing the minimum speed at which the wings can generate enough lift to maintain level flight. For the Cessna 172, like many aircraft, there are two commonly referenced stall speeds, which depend on the aircraft's configuration:
- Vs1 (Stall Speed, Clean Configuration): This refers to the stall speed when the aircraft is in its "clean" configuration. This typically means the flaps are retracted, and the landing gear is up (if retractable, though the C172 has fixed gear, so this primarily refers to flaps).
- Vso (Stall Speed, Landing Configuration): This is the stall speed when the aircraft is in its "dirty" or landing configuration. This means the flaps are fully extended, and the landing gear is down.
Key Stall Speed Values for the Cessna 172
The specific stall speeds for a Cessna 172 are detailed as follows:
| V-Speed | Description | Speed (MPH) |
|---|---|---|
| Vs1 | Stall Speed (clean configuration) | 57 |
| Vso | Stall Speed (landing configuration) | 49 |
Factors Influencing Stall Speed
The difference between Vs1 and Vso is significant and highlights how aircraft configuration impacts flight characteristics:
- Flaps: When flaps are extended, they increase the wing's lift, allowing the aircraft to fly slower without stalling. This is why Vso (with flaps extended) is lower than Vs1 (flaps retracted). Flaps are crucial for reducing landing speeds and achieving steeper descent angles.
- Weight: While not explicitly listed as a separate speed, stall speeds are typically published for the aircraft's maximum gross weight. A lighter aircraft will have a slightly lower stall speed.
- Altitude and Air Density: Stall speed is indicated airspeed (IAS). True stall speed increases with altitude due to decreasing air density, but the indicated airspeed at which the stall occurs remains constant for a given configuration.
Practical Implications
- Pilots regularly refer to these speeds during flight planning and execution.
- Understanding Vso is essential for safe landing approaches, as it dictates the minimum safe airspeed during the final descent.
- Vs1 is relevant during takeoff and en-route flight, informing decisions about minimum safe maneuvering speeds.
Understanding these speeds is fundamental to safe and efficient operation of the Cessna 172.
