Level Turning

[Avio]

Just owned the F4 for a couple of days. Even with many years of simming all types of fighters, I have much difficulty doing even level turn in the F4. Anyone managed to do this consistently?

Makes me wonder how the Thunder Birds did their formation flying.

 

[plott1964]

In the F-4E Phantom, a level, coordinated turn is primarily achieved using aileron and differential stabilator input. Rudder is generally unnecessary at high speeds but is needed at low speeds or high AoA to prevent sideslip. Back pressure on the stick maintains altitude. Overuse of rudder at high speeds can induce Dutch roll. The aircraft’s design minimizes adverse yaw, making turns mostly bank-and-pull maneuvers with selective rudder use when required.

Try using slight rudder pressure in the desired direction in coordination with slight stick movement in the opposite direction to prevent dipping.

[Yannick Pancake]

To give you a simple startingpoint in addition to the obove mentioned coordinated turns:

In general for harder turns my go to is banking to 60° and pull. If I climb I increase my AoB and if I decent I decrease it. 

 

Edited March 27 by Yannick Pancake

[Ornithopter]

Don't know if you're doing this, but don't use your Vertical Velocity Indicator as a primary instrument during a turn.  Watch your Altimeter and determine how your vertical speed is trending based on the movement of that needle, not the VVI, because the VVI lags, and so will your control inputs.

[Cab]

31 minutes ago, Ornithopter said:

Don't know if you're doing this, but don't use your Vertical Velocity Indicator as a primary instrument during a turn.  Watch your Altimeter and determine how your vertical speed is trending based on the movement of that needle, not the VVI, because the VVI lags, and so will your control inputs.

Isn’t it the opposite with the altimeter lagging the VVI?

[carbolicus]

44 minutes ago, Cab said:

Isn’t it the opposite with the altimeter lagging the VVI?

Yes, correct.

[Ornithopter]

1 hour ago, Cab said:

Isn’t it the opposite with the altimeter lagging the VVI?

 

22 minutes ago, carbolicus said:

Yes, correct.

Interesting.  The VVI is "instant" in the Phantom?  There is a table in the real F-4E manual to calculate "altimeter lag", so I'm aware there is also that.  My eyes gloss over that kind of stuff.  However, I'm not of the impression that the the VVI works instantaneously.  Are you guys sure of that?  Generally, when I'm flying level, or level turning, I'm primarily referencing the movement of the Altimeter needles, and the VVI as secondary, because otherwise I tend to Porpoise too much, hence my advice to the OP.  It seems that if I try to make small corrections based on the VVI, especially during a turn, I'll end up falling behind the needs of the aircraft, and my altitude keeping will suffer.  But I don't seem to have that problem with the Altimeter.   Frankly, I've spent too much time placing a velocity vector on the horizon line on a HUD, with planes like the Hornet, so have probably gotten very sloppy in general. 

Edited March 27 by Ornithopter

[=475FG= Dawger]

1 hour ago, Cab said:

Isn’t it the opposite with the altimeter lagging the VVI?

This is incorrect. 

Altimeter is always instantaneous. When the altimeter needle stops, that is the required pitch attitude for level flight.

There are instantaneous VVI/VSI but not all are instantaneous.

 

Does the DCS F-4 behave correctly? Who knows.

[Cab]

4 hours ago, =475FG= Dawger said:

This is incorrect. 

Altimeter is always instantaneous. When the altimeter needle stops, that is the required pitch attitude for level flight.

There are instantaneous VVI/VSI but not all are instantaneous.

 

Does the DCS F-4 behave correctly? Who knows.

Fair enough. I can't speak for all airplanes, but the ones I've flown have had the altimeter lag the VVI.

Just now, Cab said:

Fair enough. I can't speak for all airplanes, but the ones I've flown have had the altimeter lag the VVI.

I'm speaking of jet aircraft. I don't really remember props.

Also, I remember referring to it as a VSI

[Raisuli]

I've found the VVI in the F-4 to be as twitchy as a Jack Russel terrier after it got into a bag of espresso beans.  That might be accurate; I have no basis for an opinion on realism.  

When I do level turns I do use the beast, but as mentioned above pick your speed and use bank to maintain altitude.  When you think you've chased the VVI past saintly patience look at the altimeter and realize you've only drifted a little, which is probably more than allowed in the real world.  I also have no idea how much tolerance 'level' permits.

Speed is a big deal, even for flying straight and level.  When hand flying (ie no auto) 'level' is almost impossible if speed isn't fairly steady.  Trimmed up perfectly a couple extra knots either way and the VVI starts barking, so I'll get my trim where I want it and maintain 'level' with the throttle.

Still able to suck-start a nuclear reactor flying throttle for pitch on landings, though.  Probably the spooling lag.  Most of my flying issues are located somewhere between the P and the VI.

Edited March 28 by Raisuli

[Zabuzard]

The gauges are modelled very closely to the manufacturer specification documents, maint docs and test results.
The behavior was also carefully verufied by our real world Phantom pilots (inactive but also some who still fly the Phantom today).

This btw also includes their variance and how they react to forces. Speaking of, make sure you select the "reference aircraft" in the mission editor for a good base of discussion. Otherwise you might experience whatever the mission maker had set up for you.

[=475FG= Dawger]

Reading the description of the VSI in the Phantom, it has the traditional multiple second lag inherent to a VSI that does not utilize accelerometers to make it "instantaneous".

In this case the VSI (VVI) is counterproductive for trying to maintain level flight and should be ignored completely when doing so.

The altimeter is the primary reference for pitch control.

Excerpt from Heatblur manual

Edited March 28 by =475FG= Dawger

[Cab]

4 minutes ago, =475FG= Dawger said:

Reading the description of the VSI in the Phantom, it has the traditional multiple second lag inherent to a VSI that does not utilize accelerometers to make it "instantaneous".

In this case the VSI (VVI) is counterproductive for trying to maintain level flight and should be ignored completely when doing so.

The altimeter is the primary reference for pitch control.

 

https://www.mcico.com/resource-center/articles/instantaneous-vertical-speed-indicators-combat-lag-time

null

 

Excerpt from Heatblur manual

Yes, this is stimulated the little grey cells. The VSIs I was remembering were all "IVSI"s.

It's been a long time. 

[=475FG= Dawger]

1 hour ago, Cab said:

Yes, this is stimulated the little grey cells. The VSIs I was remembering were all "IVSI"s.

It's been a long time. 

I know the feeling but I seem to have a lot of aeronautical minutiae just burned into my brain. 
 

Of course, having done an extraordinary amount of partial panel in real weather might have had that effect regarding this particular topic. 

[Zabuzard]

You need to be careful with the gauges as there are different variations and they got changed over the years. So especially with consulting the standard flight manual you might need to pay attention whether it actually applies to our bird or not.

If I recall correctly, our VSI is RCS-60-1LO, which is built to meet the standard MIL-I-18804. You can find lag and error specifications and whatnot in that doc.