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28

You shut the components off to protect the sensitive electronics from electrical surges that may occur during start up of the engine. Circuit breakers are designed to trip open if too much current in amps is drawn from the power source by the electrical components or a short circuit downstream of the circuit breaker. They do not necessarily protect the ...


23

The main problem lies in the behavior of the coils inside the starter. As all inductors, they build up a magnetic field - this stored energy will cause a high spike in voltage while disconnecting. Though it can be dissipated, there is still a slight chance of damaging sensitive electronic devices. And in aeronautics one does not take chances...


22

Can you take off over gross weight? Yes, it's possible on any airplane, dependent on how far over the weight limit you are, the density altitude, how much runway you have, what obstacles are in the area and other factors. It's very easy to go above gross in a Cessna 152 with full fuel and 2 passengers, and probably happens more often than people realize or ...


19

I've worked as a technical writer on flight and maintenance manuals in a previous life. It's done with technical publications where there is a kind of quasi-legal status you might say, insofar as the information published is required for operation or maintenance, is invalid for use if not up to date, and where pages are revised, numbered and dated with a ...


15

Short answer At low speed, near the stall, 40 KIAS (the low end of the white arc) and 48 KCAS (Vs0 in the POH) refer to the same actual speed. While there is a limited divergence (0 to 2%) between CAS and IAS at medium and high speed, this difference can be as much as 20% at low speed, when the aircraft pitch is large. Details In your question, you ...


10

Are you a qualified Test Pilot with insurance covering you for crashing this aircraft? The Max Gross Weight quoted in the POH tells you how far the factory Test Pilots have taken the airplane - any further and you are doing the experimenting. (An obvious concern is that with too much weight, the wings will fold in flight. But there are other concerns.) ...


6

One thing that hasn't been mentioned yet is CG. Often CG is what will get you. On many aircraft the places that you are putting the weight has considerable arm from CG. This means that you are also shifting the CG. I have seen for instance Cessna 402 loaded amazingly over gross with the load as far to the front as possible. However Google Aaliya death and ...


5

Chapters conventionally have started on odd numbered pages, so if a chapter ends on an odd page a blank is inserted on the next even page. The reasons you'll see intentionally blank pages on digital documents are: Conventions die hard in an industry as regimented as aviation A document may be in both digital and print, there's no point in having 2 versions, ...


4

For the US under the FAA, Yes you do! From the FAA WB handbook Changes of fixed equipment may have a major effect upon the weight of the aircraft. Many aircraft are overloaded by the installation of extra radios or instruments. Fortunately, the replacement of older, heavy electronic equipment with newer, lighter types results in a weight ...


4

33.0 ft From pivot point to wingtip, it is in the POH page 1-2


4

Physically, yes the aircraft can take off at or above MTOW - and depending on the aircraft and ambient atmospheric conditions, can takeoff and fly at a considerably greater weight than MTOW. The problem becomes that the values for MTOW were decided upon during design and flight test, taking into consideration a wide range of operating conditions plus design ...


3

Critical altitude is the maximum altitude where the engine turbochargers (or turbonormalizers) can maintain sea level standard pressure to the engines. Above the critical altitude the engines will produce less power, although still delivering more power than an normally aspirated engine at the same air density.


3

There are many ways to calculate aircraft performance. Some ways are entirely manual through the use of formulas. Some ways use electronic means like apps and special calculators. Some ways use pre-calculated Tables. Then there are ways that use graphs and charts. Let’s tackle the charts way. First, remember one thing. These charts are made from data ...


3

This is a bad idea for a host of reasons, but structural failure is one of the worst. Sensitivity to gust load is increased when overweight, reducing the designers G load margin. source from Mountain Flying Consider an airplane that has a maximum allowable gross weight of 3,000 pounds. If it encounters a +30 fps gust that results in an additional ...


3

I did find a quirk alright. First off the ceiling is either 18,000 or 19,500 feet depending on the source. The video's origin is unclear, but my research hints at the narrator reading an AOPA piece (can be found on superskyrocket.com via web.archive.org): (...) later T337 and P337 models are only certified to 20,000 feet, whereas the earlier turbo models ...


3

The plane was certified with US Gallons. Use those for fuel consumption. The conversion tables are there in case your FBO's fuel pump is calibrated in L or Imp Gal.


3

There are no 100% power setting tables because it is impossible to cruise at 100% power with a normally aspirated engine. 100% power is rarely available, even at takeoff. It is only available at sea level when the temperature is 15C and the altimeter setting is 29.92".


2

The answer for the POH you provided is on this page. The page you are referencing is a revision made by someone who decided to use CAS for some reason. Your stall speeds at max gross with max forward C.G. are: Vs0 = 40KIAS Vs1 = 48KIAS


2

For conceptual design, the longitudinal CG limits can be evaluated with: Static Margin: you probably want at least 10% static margin at aft CG at the early conceptual stage for at least the flaps in configuration. Trimmability: the amount of elevators or stabilizer (if movable) required to trim both full power and power off, for all flaps. For tail mounted ...


2

You have done half of the way. Since you have computed the CG variations in all loading scenario, you know approximate limits. This limits are the ideal limit from loading and unloading point-of-view. But in real application, the design of the aircraft does not allow such broad limits. There are many factors that limits the aircraft aft CG movement: MLG ...


2

A very simple practical reason is that Vx and Vy speeds can be easily monitored as the pilot is climbing away and controlled with the elevator. This useful information is in the POH to be used by people who are quite busy at the moment, there for it is expressed in a user friendly form. Climb angle, as a matter of interest, could be studied for a variety ...


2

Because determining Vx and Vy has to do with the specific aircraft, specific power output of the engine, thrust from the propeller, etc, which is often a function of pressure altitude and airspeed. Remember that Vx represents a situation where the aircraft has the MAXIMUM EXCESS THRUST meaning a situation where the difference between the maximum thrust ...


1

This comes from the Cessna 172R POH and is typical of takeoff and landing performance calculations for all Cessna 172s. First off READ ALL OF THE RELEVANT NOTES IN THE PERFORMANCE SECTION of the AFM as they explain this in detail. But as an example, let’s assume we are departing Gerfield County airport in Rifle, CO (KRIL). It’s a warm spring day in ...


1

Generally you won't find published POH documents for plans built homebuilts, as each aircraft is unique, the individual builder being the "manufacturer". Possibly, a builder has made his own POH. Best bet is to write to the guy currently marketing the plans and selling parts, Creighton King.


1

This table is included because of the fact that the Alternate Static Port on 172s is inside the cabin. Thus, changes in cabin pressure (even really small ones) can have an impact on the static pressure that the system is using and hence on the indicated airspeed. The things the table mentions like windows and heat vents all influence the pressure in the ...


1

Typically light GA aircraft do not list normal landing distances or soft field distances in AFMs. Looking at the POH from a 172S Look at Note 3, which refers to typical soft field conditions. It indicates that a 45% increase in the short field figures is representative of soft field landing distances. As a “normal” landing distances vary depending on how ...


1

Pitch angle only corresponds to an angle or rate of climb at a particular excess thrust. Consider the typical stall exercise: you pull the engine to idle, then apply more and more elevator to try to maintain altitude, thereby pitching up and simultaneously reducing airspeed. At one point, airspeed drops to the point where you lose lift, and you fall out of ...


1

Let’s say you have an engine problem, or it’s hot and your performance is negatively effected. The angle of attack will be very different to get best climb, but the airspeed will be the same as if you have lots of power.


1

FAR Part 91, in a certificated plane, private piot in a private plane, you can fly however you'd like. Charles Lindberg taught lean of peak to pilots on WWII to save fuel for long distance ocean flights. Check the engine manual, you will find you can fly as lean of peak as you can manage. I find it hard to do with carburated O-360 engine. Usually I lean ...


1

100% power on a typical aircraft engine is only good for short durations like takeoff or emergency maneuvers. Sustained 100% power setting will destroy the engine. Not to mention flying faster is not always a good thing. It means higher aerodynamic loads on the airplane. Especially when you hit some turbulence.


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