Aircraft Performance Checklists
Next to a good preflight plan and weather report is a thorough Weight & Balance calculation. Weight and balance is a matter of serious concern to all pilots as well as many other people involved in the flight. The pilot has to personally assume the responsibility (and by law) because he has control over both the loading and fuel management, the two variable factors which can change both total weight and balance. This information is available to the pilot in the form of aircraft records, operating handbooks and placards in baggage compartments and or fuel caps. The owner of the aircraft has the responsibility to make sure that up to date information is available to the pilot.
The Aircraft Performance Checklist we present can be used for this purpose. It is very important to realize that any aircraft (yes, experimental aircraft too) which is out of balance or overweight is dangerous to fly. Not to mention deadly.
So please be very, very serious about this.
Aircraft Performance Background
Your ability to predict the performance of an airplane is very important. It allows you to determine how much runway you need for takeoff under certain conditions, if you can clear obstacles in the departure path, how long it will take you to reach a destination, how much fuel is required and how much runway is needed for landing.
Together with performance prediction you also need to observe the operating limitations of the airplane. These limits establish the boundaries in which the airplane must be flown. These limitations apply to the airplane as well as to the engines. Think of limits on takeoff power, engine / propeller rpm, temperature of oil etc. You will find these operating procedures in the airplane and engine operating manual.
Aircraft Performance Checklist
The checklist below gives a quick overview on weather, runway information and performance data for the intended flight. Use this in combination with the weight and balance form. You can use these quick reference notes (performance and weight and balance data) together with your knee board or put them on your panel so you be able to see them when you need the figures.
| Altimeter setting ________ hPa/in.hg | Surface wind _______ at _______ Kts |
| Temperature ________ C _______ F | Cross wind _______ Kts |
| Pressure Altitude ______________ Ft | Head wind _______ Kts |
| Density Altitude _______________ Ft | Winds aloft _________ at ______ Kts |
| Temp. aloft _________ C ________ F |
| Take-off: | Landing: |
| Manifold Pressure ___________ inch | Approach Speed __________ KIAS |
| Propeller Speed _____________ rpm | Runway Length ____________ ft(m) |
| Fuel Flow __________________ gph | Runway Required __________ ft(m) |
| Rotation Speed Vr __________ KIAS | Best Glide _______________ KIAS |
| Take-off Distance ___________ ft(m) | Maneuvering Speed _______ KIAS |
| Runway Length _____________ ft(m) | |
| Climb Speed _______________ KIAS | |
| Initial Climb Rate ____________ fpm | |
| Alternate Airport ________________ |
| BPH | Propeller/Manifold | KTAS | Fuel Flow | |
| Pressure Alt. ________ ft | 65% | ______rpm/____in | _____ | _____ gph |
| Pressure Alt. ________ ft | 75% | ______rpm/____in | _____ | _____ gph |
To download a pdf version click here.
Manifold pressure RPM selection
Always select a MAP/RPM combination which gives you the lowest RPM and highest MAP for a given power setting. This is equal with selecting high gear in a car. It keeps the fuel consumption and wear (RPM) of the engine low and the pressure in the cylinder higher so the rings in the piston are seated properly and the engine is working the propeller ie the other way around. Use the POH numbers and you will find that many over-square settings are acceptable. And this is also important: a lower RPM also means lower noise from the overflying aircraft on the ground.
Read more on this subject in this article.
Conclusion
By filling out these numbers you will have more control over the situation. You know what to expect from your aircraft. If any of these numbers are not met (for example: propeller speed during take-off roll or initial climb speed), then something is not right. Look for the cause before anything nasty happens. Remember: Take-offs are optional but landings are pretty much mandatory.