Excited, but at the same time disappointed

[YSoMadTovarisch]

The effect of a metal elevator is to increase the stick force gradient.  

 

End of story...that is how it works!!

 

Moment = Weight X Arm

 

Yeah, because metal control surfaces being less effected at high speed than fabric control surfaces played no part at all.

 

Also, ain't the point of this discussion was that lighter control forces at high speed were good for combat aircrafts, opposite of what you said? I'm still waiting for your rebuttal on my 2 examples.

Edited January 28, 2016 by GrapeJam

[Crump]

 

 

Also, ain't the point of this discussion was that lighter control forces at high speed were good for combat aircrafts, opposite of what you said? I'm still waiting for your rebuttal on my 2 examples.

 

No, I said 100lbs of elevator pull force was not excessive and forces that are too light are not good for combat aircraft.

[Crump]

Here GrapeJam....

 

These are the USAAF/ USN control force specifications for aircraft designers.  This is the report that set the standard used in World War II.  Now, there are other more detailed modern reports that show even more pull force can be applied.  Those studies use a larger pool of subjects IIRC.

 

[=362nd_FS=RoflSeal]

No, I said 100lbs of elevator pull force was not excessive and forces that are too light are not good for combat aircraft.

100lbs is way too much, otherwise why would fighter aircraft since the 50s that have had artifical feel controls due to hydromechanical or FBW have their control forces calibrated to the 20-40lbs range.

Edited January 28, 2016 by RoflSeal

[Crump]

100lbs is way too much, otherwise why would fighter aircraft since the 50s that have had artifical feel controls due to hydromechanical or FBW have their control forces calibrated to the 20-40lbs range.

 

 

You know, show me your source on this......

 

One of the largest problems found in FBW and hydromechanical systems is conveying the feel of flight to the pilot.  I would have to see this.  Now, I fly a large transport category aircraft.  The Yoke forces are far greater than a mere 40lbs at high speeds.  It works to keep you and the passengers safe.....

[Crump]

 

 

since the 50s

 

Transonic flight..... 

[=362nd_FS=RoflSeal]

You know, show me your source on this......

 

One of the largest problems found in FBW and hydromechanical systems is conveying the feel of flight to the pilot.  I would have to see this.  Now, I fly a large transport category aircraft.  The Yoke forces are far greater than a mere 40lbs at high speeds.  It works to keep you and the passengers safe.....

Stop comparing a fighter aircraft with a transport aircraft that will probably never pull more then 2G's.

 

F-15 CAS stays at a constant 3.75lb/g, Su-27 FBW calibrated stick forces is about similar till 8.5G then you need to pull ~60lbs to pull 8.5 to 9G+. I can't find the figures on me but the F-86F Sabre's elevator was very light, 3-4lbs/G , F-16 stick is even lighter at 2.6lb/G. Saying 100lbs at high speed is alright is completely bollocks. Experience doesn't show this, modern fighter aircraft don't approach that figure, even aircraft that have soft limiters in their FBW like Su-27 and Mirage.

Edited January 28, 2016 by RoflSeal

[Crump]

Stop comparing a fighter aircraft with a transport aircraft that will probably never pull more then 2G's.

 

F-15 CAS stays at a constant 3.75lb/g, Su-27 FBW calibrated stick forces is about similar till 8.5G then you need to pull ~60lbs to pull 8.5 to 9G+. I can't find the figures on me but the F-86F Sabre's elevator was very light, 3-4lbs/G , F-16 stick is even lighter at 2.6lb/G. Saying 100lbs at high speed is alright is completely bollocks. Experience doesn't show this, modern fighter aircraft don't approach that figure, even aircraft that have soft limiters in their FBW like Su-27 and Mirage.

 

The large transport catagory aircraft comparison was because you just made a statement without any facts to back it up.  I was simply wondering what the specifics you were talking about.

 

Yes, the Stability and Control engineering of relaxed stability FBW, supersonic, and transonic aircraft have little to do with the subsonic conventional control systems of World War II fighters.  None of them had stabilator systems for transonic flight of say the F-86 and just about every other transonic/supersonic design.

 

What I said about 75lbs to 100 lbs of pull force being easily attained is presented by the facts and measured data  for subsonic aircraft designs with conventional control systems....

 

You can hate me and go put pins in a little cupie doll of my likeness if it makes you feel any better!  

 

It does not change the measured data or the facts.

 

IIRC, the minimum stick force per G in an unlimited aerobatic aircraft with conventional controls is on the order of 8lbs per G.  That will get you 100lbs of pull force.....

 

 

 

Edited January 28, 2016 by Crump