MeteoSwiss: Summer weather = pay attention to density altitude

Rapid weather changes require increased attention when planning flights. Sometimes, meteorological details can slip out of focus. Last weekend, Switzerland experienced its first hot days of the year with temperatures above 30 degrees Celsius. This makes the topic of “density altitude” even more relevant. Please pay special attention to this aspect in your flight planning on hot days.

By the way, hot temperatures not only have a significant impact on engine performance during takeoff or cruise flight, but also on the flight and control characteristics of an aircraft during landing.

Higher landing speed
Due to the thinner air, the wings generate less lift at a given indicated airspeed (IAS). The TAS (true airspeed) for the same IAS is higher, which leads to more kinetic energy on touchdown → longer braking distance.

Longer landing distance
The higher approach speed and lower braking effect of the air mean that an aircraft needs more runway. This is particularly critical on short or high-altitude runways (e.g., in mountains).

Reduced control effect
Control surfaces (rudder, elevator, ailerons) respond sluggishly because the air density is lower. Sensitive control during touchdown can be difficult.

You can find more information and tips in the articles from previous years:

Sommerzeit: Grosse Hitze, kleine Leistung und richtige Flugtaktik

Summertime = High-Density-Altitude-Time

Fliegen in der Hitze: Density altitude und die “Backside of the Power Curve”