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How do I read the measurements and statistics/gauges in a jet?
I am a student who is interested in being in the US AirForce. #military-pilot
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Ld’s Answer
Hi Justin,
If I were you, I'd go take an "introductory flight" at your local airport in a Cessna or some light, single-engine aircraft. Get your instructor to go through the "4 forces," the "six-pack gauges," and basic flight maneuvers with you on the ground BEFORE climbing into the plane. A 30-minute discussion with an instructor can answer a ton of your questions. They will want to just go straight to the airplane -- don't let them get away with that. Go through it beforehand and then go flying. The four forces are: lift, weight, thrust, and drag. The six-pack gauges are: altimeter, airspeed, vertical speed, attitude, turn/bank, and heading indicator. All fixed-wing aircraft (i.e., regular airplanes) will have these gauges in some configuration or another; they may look different from one cockpit to the next, but they'll be there. Airspeed is just that: "speed through the air." The plane is affected by ambient wind, so your "ground speed" may be more or less than "indicated airspeed." Vertical speed shows trends of how quickly you're climbing or descending. If you're straight and level, it will point to 0, and it shows the trend in climb or descent if "feet per minute" (fpm). Turn/bank will show the rate of your turn and bank in relation to what is called a "standard rate turn" of 3 degrees per second. Don't worry about this right now - you'll need a more in-depth discussion than what I'll provide here. The altimeter can actually be manually adjusted to account for the ambient pressure in the atmosphere, but if adjusted properly, it registers your height above mean sea level...NOT the ground. FYI, that means you'll need to know what the elevation of the ground is below you to figure out how high you really are above it! The heading indicator can also be manually adjusted to match the wet compass, which will also be somewhere in the cockpit. The reason for this is because the actual gauge is powered by a gyroscope and will tend to precess over time. When you start the plane up, the gyro powers up, and the heading indicator may be much different from the wet compass. Line the two up BEFORE you go flying! Lastly, the attitude indicator (also gyro powered) shows angle of bank and pitch all in one ("pitch" is nose up or nose down). With regard to the other instruments, you'll have RPM in a piston-powered aircraft, and "engine pressure ratio" or "exhaust gas temperature" as well as other engine performance indicators in jets. For each jet, there will be different settings to achieve optimum performance for a specific part of the flight. But it will be dependent upon ambient temperature, pressure, aircraft weight, etc. I.e., you may not want the throttles all the way forward for takeoff in a jet; instead, you'll "set" a specific engine pressure ratio setting (which is going to be near max power) to achieve maximum thrust. It depends on the jet as to what that setting is.
Whew!
Okay...that's the "ultra-condensed" version! Go take a 30-minute intro flight if you can, and have the instructor give you a brief over this stuff when you're there. If that person is really interested in teaching you, he or she should not have a problem talking to you about these concepts. Even if you can't afford a 30 minute flight or if there's another reason you can't do the flight, at least get 30 minutes or so with an instructor on the ground. They'll charge you, but it will be cheaper and will answer a ton of questions in a short period. Best of luck!
If I were you, I'd go take an "introductory flight" at your local airport in a Cessna or some light, single-engine aircraft. Get your instructor to go through the "4 forces," the "six-pack gauges," and basic flight maneuvers with you on the ground BEFORE climbing into the plane. A 30-minute discussion with an instructor can answer a ton of your questions. They will want to just go straight to the airplane -- don't let them get away with that. Go through it beforehand and then go flying. The four forces are: lift, weight, thrust, and drag. The six-pack gauges are: altimeter, airspeed, vertical speed, attitude, turn/bank, and heading indicator. All fixed-wing aircraft (i.e., regular airplanes) will have these gauges in some configuration or another; they may look different from one cockpit to the next, but they'll be there. Airspeed is just that: "speed through the air." The plane is affected by ambient wind, so your "ground speed" may be more or less than "indicated airspeed." Vertical speed shows trends of how quickly you're climbing or descending. If you're straight and level, it will point to 0, and it shows the trend in climb or descent if "feet per minute" (fpm). Turn/bank will show the rate of your turn and bank in relation to what is called a "standard rate turn" of 3 degrees per second. Don't worry about this right now - you'll need a more in-depth discussion than what I'll provide here. The altimeter can actually be manually adjusted to account for the ambient pressure in the atmosphere, but if adjusted properly, it registers your height above mean sea level...NOT the ground. FYI, that means you'll need to know what the elevation of the ground is below you to figure out how high you really are above it! The heading indicator can also be manually adjusted to match the wet compass, which will also be somewhere in the cockpit. The reason for this is because the actual gauge is powered by a gyroscope and will tend to precess over time. When you start the plane up, the gyro powers up, and the heading indicator may be much different from the wet compass. Line the two up BEFORE you go flying! Lastly, the attitude indicator (also gyro powered) shows angle of bank and pitch all in one ("pitch" is nose up or nose down). With regard to the other instruments, you'll have RPM in a piston-powered aircraft, and "engine pressure ratio" or "exhaust gas temperature" as well as other engine performance indicators in jets. For each jet, there will be different settings to achieve optimum performance for a specific part of the flight. But it will be dependent upon ambient temperature, pressure, aircraft weight, etc. I.e., you may not want the throttles all the way forward for takeoff in a jet; instead, you'll "set" a specific engine pressure ratio setting (which is going to be near max power) to achieve maximum thrust. It depends on the jet as to what that setting is.
Whew!
Okay...that's the "ultra-condensed" version! Go take a 30-minute intro flight if you can, and have the instructor give you a brief over this stuff when you're there. If that person is really interested in teaching you, he or she should not have a problem talking to you about these concepts. Even if you can't afford a 30 minute flight or if there's another reason you can't do the flight, at least get 30 minutes or so with an instructor on the ground. They'll charge you, but it will be cheaper and will answer a ton of questions in a short period. Best of luck!