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Aircraft stall aftter disengaging APP


cloaking
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Hey

 

Usually I'm allways flying on ILS. When I have the glideslope from the ILS and approaching approx 400 above the runway I disengage APP and AP button to do the approach manually.

Suddenly my aircraft (ex stock 777) stalls upwards.:confused:

Normally my speed is around 145-150knots.

 

What causes this? Is it something to do in the aircraft.cfg and/or panel.cfg ?

 

Thx in advance

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Hey

 

Usually I'm allways flying on ILS. When I have the glideslope from the ILS and approaching approx 400 above the runway I disengage APP and AP button to do the approach manually.

Suddenly my aircraft (ex stock 777) stalls upwards.:confused:

Normally my speed is around 145-150knots.

 

What causes this? Is it something to do in the aircraft.cfg and/or panel.cfg ?

 

Thx in advance

 

You're too slow. Simple.

Approach at about 180 knots. And adust the load to reduce pax and/or fuel weight.

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APP is the autopilot Approach Mode button.

@cloaking, if you're stalling on approach you're probably at or below the 777's stall speed - try approaching at 160-170kias instead.

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Yes, it sounds like you are just on the verge of a stall and that the autopilot is just managing it.

Then you turn off the autopilot, give a bit of elevator or roll input and there you go.

 

How are you configured on approach? What flap setting?

 

How heavy are you?

If you carry too much cargo and/or fuel on arrival you will need to fly faster and will stall earlier.

 

Does your 777 come with an angle of attack indicator?

Edited by jeroen79
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It's me again

 

I just went to http://www.fuelplanner.com and did a calculation from LOWI towards LIRA in a 747-400.

There it mentioned the needed fuel :24712 lbs reserve:25936 fuel on board:50648.

Now my question is how do you put those parameters into the fuel option ? Left,center,right enz to get those values? Maybe that's the reason why all;my planes starts pitching down and up when i release the autopilot and approch button. I'm to heavy, I start allways flying with full tanks.

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So how heavy are you on arrival and where is the center of gravity?

How much fuel and cargo are you carrying at that point?

What is your speed when you turn off the autopilot on approach?

 

When you are heavier you will stall earlier and you will need to fly faster.

A quick google comes up with 623000 pounds max landing weight.

 

Flying the whole approach on autopilot will hide from you how the plane is flying.

This can lead to a surpise when you suddenly turn it off.

Try hand flying it (like from the top od descent) and see how the plane behaves.

If you find that you cannot keep the plane up at a given speed add some power to increase speed.

 

 

That planner seems to make some assumptions about the weight of the aircraft, the cargo and it's fuel consumption.

It will tell you how much fuel it will take to go from departure to arrival and how much reserve you carry.

This figure may not match with your aircraft and loadout in the sim.

Check for yourself how much fuel is actually consumed.

 

It is up to you to divide that fuel over the available tanks.

For example, if the planner recommends 13k lbs of fuel then you could put 5k in the left tank, 5k in the right tank and 3k in the center tank.

Watch the center of gravity while you do this.

 

 

What is your current experience in sim flying?

How did you start and what have you done before the 747?

How do you prepare for a flight?

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It's me again

 

I just went to http://www.fuelplanner.com and did a calculation from LOWI towards LIRA in a 747-400.

There it mentioned the needed fuel :24712 lbs reserve:25936 fuel on board:50648.

Now my question is how do you put those parameters into the fuel option ? Left,center,right enz to get those values? Maybe that's the reason why all;my planes starts pitching down and up when i release the autopilot and approch button. I'm to heavy, I start allways flying with full tanks.

 

You state that you 'always flying with full tanks'

That would be fine if you were doing a massively long half way round the world flight, but your flight from LOWI to LIRA is in the hundreds of miles (not sure of exact distance )a short hop for a 747.

Your problem (I think)is that after such a short flight LOWI LIRA by the time of your approach and landing you are to heavy (with fuel)and to slow ,and on disengaging autopilot you stall and crash.

 

Cheers Andrew

Edited by HoratioWondersocks
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You state that you 'always flying with full tanks'

That would be fine if you were doing a massively long half way round the world flight, but your flight from LOWI to LIRA is in the hundreds of miles (not sure of exact distance )a short hop for a 747.

Your problem (I think)is that after such a short flight LOWI LIRA by the time of your approach and landing you are to heavy (with fuel)and to slow ,and on disengaging autopilot you stall and crash.

 

Cheers Andrew

 

Put the chosen amount in the tanks, no more.

Starting with full tanks is a fundamental error.

 

The 747 carries about 238,000 litres for about 9,500 miles.

FAR too much for a short trip from LOWI to LIRA (call it about 334 nautical miles, no more)!

 

Plan for about 1 galllon per second. Do NOT carry more than you need.

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Hello Mr cloaking

Concerning approach speeds

If you need help with approach speeds, takeoff,cruise, decent etc I can recommend some very good freeware guides by a man called Werner Schott.

These guides cover all the major popular airliners and lots of other aircraft as well.(They are specifically for flightsim users)

You can even print them out ,or as I do store them on my android tablet.

I have had them for years ,and still refer to them from time to time.

They won't help with your fuel loads, but a freeware program called fuel loader will and make the whole process much easier than using Fs9 default.(although you will still have to get an idea of the correct amount you will need for any given flight )There are plenty of folks here who can help you with that though.

Not sure if it's available here at FScom library, but iam sure it is there at the other place (whispers) Avsim.

 

Cheers Andy

Edited by HoratioWondersocks
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