A detailed article explaining the relationship between aircraft attitude, power and performance. We will take a look at each of the three variables separately and then at how they interact with one another.
One of the most basic mantra’s taught to students during their flight training is that power plus attitude equals performance. The basic concept is that if a pilot sets a particular attitude and a particular power setting, the aircraft will give a particular performance for a given weight and configuration. This is particularly useful during emergency situations or periods of high workload where sensory overload is more likely to take place.
Also, some pilots appear to effortlessly fly the aircraft while some keep constantly fighting the aircraft with large and abrupt control inputs. The key to smooth and effortless flying is attitude flying which entails setting a particular attitude and then observing what the flight instruments do and then making small corrections. This technique prevents over-controlling, making excessive and large inputs, and chasing instruments.
This article will take a look at each of the three variables separately and then at how they interact with one another. Some tips for attitude flying will also be discussed in the article.
For more information on attitude flying, you can check out American Flyers.com1.
What Is Power?
In simple terms, controlling an aircraft requires the ability to control power and attitude. Power is relatively easy to control using the throttle, confirmed by instruments (such as Tacho RPM, manifold pressure or torque gauge). Although with experience, you will develop a feel for known throttle position, an ear for engine revs and a feel for acceleration.
Attitude is more difficult to control accurately, but provided you’re paying close attention to it directly, instead of focusing on the instruments, it will become instinctive. Here we primarily refer to the pitch atittude, that is the position of the aircraft nose relative to the horizon (above or below it).
This training method is broken up into power control followed by each element of attitude control – instead of the usual straight and level flight, climbing, descending, turning, etc is taught in stages. By learning how to control power and reach desired attitude in all the planes of movement, you’ll know how any maneuver can be performed skillfully, instead of having to learn each separately.
What Is Pitch Attitude?
Pitch attitude is defined as the relationship of the aircraft to the natural horizon as perceived through the windscreen. It is infinitely variable through various combinations of pitch, roll and yaw through the full range of movement about each axis. The objective is to control the airplane’s attitude so its movement is confined to the range of movement desired and nothing more.
During their early days in training, students are taught in a variety of ways how to determine their pitch attitude while flying and referencing the earth’s horizon, and the bank angle. One such way is to develop a sight picture of what the student should see if he / she is flying at different pitch attitudes.
Another technique is the use of fingers as an attitude indicator or one can simply use the cowling in relation to the horizon to gain a good idea of the pitch attitude.
What Is Aircraft Performance?
Aircraft performance can be defined as the ability of an aircraft to carry out certain tasks under a given set of conditions. Aircraft performance covers the entire regime of the flight sequence from takeoff to landing.
Modern aircraft are designed with strict adherence to national and international standards as defined by International Civil Aviation Organization (ICAO) Annex 8. These stipulations define the standard that the manufacturer must adhere to while manufacturing an aircraft meant for commercial use.
Normally, an aircraft delivers its peak performance at cold temperatures, low elevation, and low altitude where the air is dense. The relationship between peak performance and low altitude can be understood by the following equation:
Density = Mass / Volume
Force = Mass x Acceleration
Based on the two equations above, we can see that the air density is directly proportional to mass. As density increases, mass flow through the engine increases and as a result the engine develops more thrust which propels the aircraft forward.
Adversely, the worst combination for aircraft performance is hot temperatures, high altitude, and high elevation as the air tends to be less dense and less thrust is produced as a consequence.
To find out more about aircraft performance, check out Skybrary2.
Alternatively, you can also have a look at the info from FAA.gov3.
What is the relation between power and pitch and performance?
The relation between pitch and power is directly proportional. In order to increase pitch and maintain that pitch attitude, power will be required otherwise the aircraft will start to lose its kinetic energy and might enter a stall if the critical angle of attack is exceeded.
Flying in the slow speed regime or the back end of the power curve as it is more commonly known, requires a delicate balance between precise pitch control and power. In this regime, pitch controls airspeed and power controls rate of descent / rate of climb. At normal cruise speeds and during approaches, students are taught to use power for airspeed and pitch for rate of descent.
Modern engines are either temperature limited or pressure limited. Engines are temperature limited at high altitudes and high temperatures and at low altitudes they are limited by the amount of power they are able to produce under the given circumstances.
There is a limit to how much power an engine can produce under a given set of circumstances. Once all the available power is depleted, the engine will not be able to deliver the required power and performance.
To gain a better understanding of the relationship between power, pitch and performance, visit Pilot Workshop.4
More info can also be found at The Bold Method5.
The combination of power, pitch and performance is not only applicable in emergency events but also in routine flying operations, for full aircraft control. It is vital that pilots know the pitch and power settings for any phase of flight, should there be any failure.
Pilots should also develop the habit of making a mental “sight picture” of various attitudes as well as be able to set power settings based on the engine’s sound and throttle lever position.
- ‘Attitude Flying: Establishing Control of the Aircraft’s Flight Path’, Steven Daun, American Flyers. Published: August 22, 2020. Accessed online at https://americanflyers.com/attitude-flying-establishing-control-of-the-aircrafts-flight-path/#:~:text=Pitch%20(attitude)%20%2B%20power%20%3D,consistently%20provide%20the%20desired%20performance on November 29, 2022.
- ‘Aircraft Performance’, Skybrary. Accessed online at https://www.skybrary.aero/articles/aircraft-performance on November 29, 2022.
- ‘Aircraft Performance’, FAA.gov. Accessed online at https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/13_phak_ch11.pdf on November 29, 2022.
- ‘Pitch or Power’, Bob Nardiello, Pilot Workshops. Accessed online at https://pilotworkshop.com/tips/pitch-or-power/ on November 29, 2022.
- ‘Pitch For Airspeed, Power For Glideslope? Or The Other Way Around?’, Aleks Udris, Bold Method. Published: November 28, 2019. Accessed online at https://www.boldmethod.com/learn-to-fly/navigation/how-to-control-pitch-and-power-on-a-glideslope-to-landing/ on November 29, 2022.
- ‘Aircraft for Amateurs’, FAS.org. Accessed online at https://man.fas.org/dod-101/sys/ac/intro.htm on November 29, 2022.