Wolfie6020

Wolfie is a FAA and CASA rated ATP Licenced pilot, currently flying the latest Bombardier Global Express business jet. He also has a CASA Commertial Helicopter Licence. He has more than 10,000 hours (3000 on helicopters) flight time. He is a Grade 1 Flight Instructor and Air Crash Investigator.

A look inside the Artificial Horizon - Pendulous Vanes

Any time the the gyro is not aligned with true level the pendulous vanes will swing slightly to open one air port more than the other. This results in a correcting force that brings the unit back into alignment with true level.

The pendulous vanes do not care what causes the misalignment which may be due to precession, harsh manouvers, extended periods of turning or the movement across the curvature of the Earth. They simply act to correct the misalignment. In this way they are constantly correcting the attitude indicator to remain level as the aircraft moves around the curvature of the Earth.

Airborne Weather Radar, evidence of Earth's curvature

Airborne Weather Radar at zero tilt will scan an angle 2.8 degrees down from Level. At 290 Miles from Hawaii the Mountains should be visible on the Radar with zero tilt if the Earth was Flat - the angle from aircraft to the base of the Mountains is 1.7 degrees.

However with zero tilt they are not visible. We need to tilt the radar down 3 degrees to see the Mountains clearly. This is because the earth is a Globe.

Airplane Approach Calculations take the Curvature of the Earth into account

Some airports use GNSS (GPS) non precision approach (NPA) and ILS (radio beacon) precision approach (PA) vertical guidance for the final approach to the runway. ILS is a straight line approach, while GNSS is a curved line approach following the curvature of the earth on a glide slope angle. In the calculations of the distance from the runway to the final approach point the curvature of the earth is taken into account for both approach variants.

Analysing Aircraft Flight Paths correctly. Flat Earth or Globe? Where do they make sense?

I see many Flat Earth sites trying to understand why the flight paths are curved on a Flat Map.

The answer is simple - because a Flat Map is a distortion of the true shape of the Earth which is a Globe. Flight paths plotted accurately on a Globe make perfect sense.

Artificial Horizon self corrects in flight

This video proves an aircraft Artificial Horizon will rapidly correct alignment errors in roll and pitch. It has self correcting mechanisms that will constantly keep it aligned to the local level. The corrections occur at the rate of 2-4 degrees per minute. For the Gyro to remain level as an aircraft flys over the curved Earth at 450 Knots only one degree of correction is needed every 8 minutes.

Cloudy Horizon appears below an Airplane 25 miles ahead 2000 feet below us

Fying at an altitude 2000 feet above another airplane 25 miles ahead, as indicated by the TCAS system, we see not only the other airplane below our eye level, but the clouds and the horizon in the distance appear way below the other airplane. This proves that the horizon does not raise to eye level or true level as indicated by the Head-up display (HUD).

The Enhanced vision system (EVS) of the HUD uses infrared to look through the haze to be able to display where the real horizon is. It is indicaded well below true level.

Curved Horizon drop demonstrated at Night on the Head-up Display

Just another video proving the horizon does not always rise to eye level. The drop at 43,000 ft altitude is about 3.6°, as shown on the Head-up display (HUD) of my aircraft. At this night just after sunset the horizon was very clearly visible and matched exactly the horizon of the Enhanced vision system (EVS) of the HUD. We could even clearly see the left to right curvature of the horizon from that altitude.

Do aircraft change attitude to follow the curvature of the Earth?

The answer is yes the aircraft does change attitude as it cruises along the curved Earth.

An average pilot will never notice this as the rate of attitude change is so slow it is undetectable to the human senses. The pilot will never be conscious of pushing the nose down to follow curvature as the necessary change in attitude occurs simply by the action taken to maintain a constant altitude.

Does weight change with Latitude? Is this evidence the Earth is spinning?

If the earth rotates around its axis there should be a centrifugal acceleration outward reducing the effective gravitational attraction, depending on the latitude. This reduction is big enough so it can be measured with a good scale.

This reduction in gravity due to centrifugal acceleration is called the Eötvös effect. Because of this effect scales have to be calibrated for the latitude they are being used.

I have used a precision scale at multiple locations to demonstrate this effect is real.