Gear Up Flight

I dont know either why this happens but a thought that just have pass from my mind, is that maybe they have gears down because most of the experimental or demostration flights are in low altitude ,so in order to be ready for an emergency land they have the gears down.Maybe of course my thought is totally wrong.Im waiting also to see a post of someone who really knows the reason.

crosscheck9 wrote:

PS: Radarman, I recently posted a few unrelated topics in the General section, which you had moved. I only discovered the new "Off Topic" forum yesterday. My apologies.

Not a problem, I just moved them. That way it leaves this forum open for flight questions.

I know the reason why the A380 flew with the landing gear down for a few minutes. The A380 took off and the pilots didn't raise the landing gear until 10,000 ft. This was because, if I remember well, they wanted to have more weight and test the aircraft with even more weight. This is good to test airplanes because pilots need to have the skill of flying airplanes with loads of weight.

The highest altitude that the A380 flew was 27,000 ft or FL270.

I knew i was wrong....

😉

Your answer makes sense, though. 😉

Very kind of you Agus. 😉 Thanks a lot.

You're welcome, Greekman! 😉

Agus0404 wrote:

I know the reason why the A380 flew with the landing gear down for a few minutes. The A380 took off and the pilots didn't raise the landing gear until 10,000 ft. This was because, if I remember well, they wanted to have more weight and test the aircraft with even more weight. This is good to test airplanes because pilots need to have the skill of flying airplanes with loads of weight.

The highest altitude that the A380 flew was 27,000 ft or FL270.

Interesting

Thanks for that Agus 😉

You're welcome!

I have a tape of the A380 Maiden Flight with all that information.

Before the pilots decided to land, the flew to 3000 ft ASL so that the people can cheer and clap and watch that giant bird pass by. After that the pilots performed the approach to Toulouse Airport and the aircraft landed safely. It was a successfull test flight.

It's a nice story....the biggest commercial aircraft with the world's heaviest weight took off and everything was fine. No failures.

The gear also adds drag to the airplane and causes it to be more unstable than clean. It is primarily to test the most critical phase of flight, take-off and landing.

How does having the gears down add more weight?

Drag makes sense

It also add weight. Do you think that the gears have no weight? They are heavy. Gears also add drag. Both answers make sense.

I will see the funny side of your comment 😂

What I don't understand is how gears down add's more weight. The gears are still attatched whether up or down.

This is just something I don't understand and I think my question was a fairly logical one.

It was a logical question.

I can't tell you the exact answer with all the physics and everything because I heard an A380 pilot saying that after the aircraft landed.
As I said....

This was because, if I remember well, they wanted to have more weight

I don't remember everything this pilot said, but I do remember that he said that the gears down added more weight to the aircraft.

It's a long time since I was at school but I am sure that in engineering physics there was something about altering the shape of matter and therefore altering the centre of gravity and altering the virtual weight of that matter. As the shape of the aircraft is altered by lowering or raising the landing gear then this will alter the virtual weight of the aircraft - or am thinking of something else?
This is, of course quite separate from the question of drag.

The CG would shift down slightly. Perhaps the increased drag made the craft feel heavy. 🙂

Greetings all!

When taking a new and "unproven" aeroplane on it's first test flight, the last thing you want is begin changeing it's configuration too soon (= too low). You really want to avoid any unexpected or uncalculated or never-having-shown-up-in-simulation changes of trim at low altitude. Remember: however much a new aeroplane has been tried out in simulation, the first real world test flight might still show utterly unexpected reactions to any change in configuration, or even slight movements of the control surfaces.

I'd much rather have that happen at a more or less decent altitude, than at 200 feet or so!

Be well!

Jaap Verduijn.