Vcc is commonly known as “enroute climb speed,” and it’s generally faster than Vy. Unless a steep climb is necessary to avoid terrain or to follow a departure procedure, cruise climb speeds enable you to fly at a higher speed while experiencing a relatively minor reduction in climb performance.
Once you’ve reached the pattern altitude or 1,000′, transitioning to cruise climb speed might be a wise choice.
So which aircraft have a cruise climb speed, and which types of aircraft benefit the most from it? We’ll explore that shortly, but first…
The Benefits of Flying Vcc
Cruise climb offers several advantages. Firstly, increased airflow helps keep your engine cooler during the climb, which is particularly crucial for high-performance piston aircraft.
Secondly, it gets you to your destination faster. Although you do sacrifice some climb performance, in most aircraft, the loss is acceptable, and in some cases, it’s almost imperceptible, in exchange for a faster forward airspeed during the climb.
Finally, you enjoy better forward visibility in a cruise climb. After all, you’re supposed to be looking out the window for traffic. Additionally, a reduced pitch attitude can make your passengers feel more relaxed. If you’re flying an unpressurized aircraft, the reduced rate of climb can also help mitigate the pressure changes that your passengers experience. Remember this tip if you have a sick passenger, a young child, or a baby on board.
When Is a Cruise Climb Speed Published?
This depends on the aircraft, but generally speaking, the higher the performance, the more likely there is a published cruise climb speed.
Even the Cessna 172S has a recommendation for cruise climbs. The 172’s sea-level Vy is published at 74 knots. Enroute climb (Vcc) is published at 75-85 knots. Here’s a quote from the POH…
“Normal enroute climbs are performed with flaps up and full throttle and at speeds 5 to 10 knots higher than the best rate-of-climb speeds for the best combination of performance, visibility, and engine cooling.”
An Easy Rule of Thumb If You Don’t Have a Published Vcc
If you want to determine the cruise climb speed for your aircraft and don’t have a published speed, a good rule of thumb is to find the difference between Vx and Vy and add that number to Vy.
For example, a POH for the Piper Warrior III has a Vy of 79 knots and a Vx of 63 knots. Adding the difference of 16 knots to Vy gives an estimated cruise climb speed of around 95 knots. Depending on weight and performance, 95 knots might be a bit on the high side, but it’s a good starting point. It also provides a speed you can experiment with during the climb.
How Exactly Does Performance Change?
To analyze the performance change, let’s take a look at a POH that has both rates published: the Cessna 208EX Caravan. Although the Caravan may be different from what you fly, the performance change is actually very similar in most single-engine aircraft.
Let’s start with climb rates. Here are the conditions: 8,000 foot pressure altitude, 20 degrees Celsius, and maximum takeoff weight of 8,807 pounds.
- Vy (102 knots): 740 feet per minute
- Vcc (115 knots): 675 feet per minute
With this scenario, you only lose 65 feet per minute in climb rate, in exchange for 13 knots more airspeed. This equates to 12% more speed with an 8% reduction in FPM.
What about time, fuel, and distance for climb? Here are the conditions: climb from sea level to 8,000 feet, standard temperature, and maximum weight.
- Vy: 7 minutes, 61 pounds of fuel, and 13 nautical miles
- Vcc: 7 minutes, 62 pounds of fuel, and 14 nautical miles
In this example, the time to climb is essentially the same, you’ll only burn about 2% more fuel, and you’ll have over 7% faster forward airspeed.
Although this example is based on the Cessna Caravan, in most aircraft, you’ll find that the percentage change in FPM is relatively small compared to the significantly improved airspeed achieved during cruise climb.
Swayne Martin
A Cooler and Faster Climb Speed
If you have the capability to fly a cruise climb departure, you can shorten your trip time, keep your engine in better condition, and make your passengers in the back more comfortable.
Does your plane have a cruise climb speed? How much of a difference does it make compared to Vy? Let us know in the comments below.
