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rennman

Captainsim 707 high pitch in cruise.

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Hi. The 707 has a very high pitch in cruise. (Not quite 5 degrees, but almost.)

I tried with light payload and same thing.

 

Any ideas?

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I had a few flights (as pax) in 707s back in their heyday and they certainly cruised with a fairly high nose-up pitch. In fact the first time I flew in one (my first time in any passenger jet) I thought we were still in the climb when clearly we had been in cruise for quite a while!

Bill 

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Well if you noticed that in real life, I will thank Captainsim for keeping it real!

I wonder why boeing designs it like that though...it's uncomfortable for passengers?

Thanks again.

 

 

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2 hours ago, rennman said:

Well if you noticed that in real life, I will thank Captainsim for keeping it real!

I wonder why boeing designs it like that though...it's uncomfortable for passengers?

Thanks again.

 

 

Most jet airliners fly with a nose up pitch of maybe 2 to 3 degrees as they have to maintain a minimum angle of attack to achieve a degree of lift from the wings equal to the weight of the aircraft, so it is not unique to the 707. As I understand it, at high altitudes where the air is less dense that angle may need to be slightly more than at low level. It isn't uncomfortable as a passenger as the nose up pitch is relatively slight and but in some airliners if you are looking forwards in the cabin you might notice that it is slightly uphill, particularly if it is a long cabin unbroken by bulkheads.

Bill

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Posted (edited)

There is/was nothing wrong with the real world deck angle on the  B707.  🙂

As far as flight sim goes, I thought the HJG B707 was much better than the Captain Sim B707.

Edited by BlueStar

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13 hours ago, scianoir said:

Most jet airliners fly with a nose up pitch of maybe 2 to 3 degrees as they have to maintain a minimum angle of attack to achieve a degree of lift from the wings equal to the weight of the aircraft, so it is not unique to the 707. As I understand it, at high altitudes where the air is less dense that angle may need to be slightly more than at low level.

Nose up pitch has not much to do with wing lift, since it's the incidence angle of the wing and its washout which is important.

The attitude difference for level flight is very high concerning speed, weight and altitude.

E.g. a 767 at 30000ft at M.78 and low weight requires 1deg pitch, while the same cruising speed at 40000ft and high weight requires 4deg pitch.

@rennman, there should be a 1-2deg difference between low and high weight for the same altitude and speed.

That said, Captainsim isn't exactly famous for the flight models 😉 

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On ‎4‎/‎23‎/‎2019 at 6:16 AM, FDEdev said:

Nose up pitch has not much to do with wing lift, since it's the incidence angle of the wing and its washout which is important.

The attitude difference for level flight is very high concerning speed, weight and altitude.

E.g. a 767 at 30000ft at M.78 and low weight requires 1deg pitch, while the same cruising speed at 40000ft and high weight requires 4deg pitch. 

@rennman, there should be a 1-2deg difference between low and high weight for the same altitude and speed.

That said, Captainsim isn't exactly famous for the flight models 😉 

Just to clarify the definitions for rennman in case he is not familiar with them the angle of incidence and angle of attack are not the same.

The angle of incidence is the angle formed by the chord line of the wing and the longitudinal axis of the aircraft and it is fixed by the manufacturer during design. In airliners the angle of incidence is generally designed to be as small as possible to minimise nose up pitch during cruise.

The angle of attack is the angle between the chord line of the of the wing and the direction of the relative airflow and this is what changes when pitch is altered and, as FDEdev says, this will vary depending on speed, weight and altitude.

BTW I tend to agree regarding Captain Sim's flight models (just contrast the flight dynamics/characteristics of the CS and PMDG 777s) but I think they have managed to create a reasonably realistic cruise pitch for the 707.

Bill

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