question on (109) elevator compression

[jodgi]

Originally posted by MiloMorai
I know Angus, but wanted to make people think a little more deeply.

You fascinated by Socrates?

[GODO]

One thing is the force needed to move a control surface, and other is the force that you can really apply due the stick and cockpit design.

AFAIK The problem with the 109 was not related to very hi forces on the surface control, but to the lack of room to apply enough force to the stick laterally (aileron control). Here you will find a clear view of the 109G6 cockpit design and certainly there is very little lateral room, but, on the other hand, the space to apply forward and rearward forces to the stick seems more than enough, so, elevators should not suffer of the same effect.

109G6 cockpit

Even better view:

109G6 cockpit

[HoHun]

Hi Milo,

>How effective can the elevator be if the pilot due to excessive force cannot readily make the elevator move?

Tough question :-)

What the high control force actually does is to limit the throw of the control surface - it can be deflected, but only by a small measure.

However, at high speeds, small deflections can actually have large results anyway, so large control force doesn't necessarily mean poor control response.

With regard to the Me 109, there's a bit of a contradiction in the reports regarding its aileron effectiveness at high speed. It's generally considered poor, yet at very high Mach numbers the ailerons actually became overbalanced.

(In other words, they but they actually deflected themselves if left alone!)

The funny thing is that this means that at Mach numbers slightly below the speed where over-balancing began, I'd expect the Me 109 to have balanced (and accordingly very light) ailerons.

I don't know what to make of this, I've just stored it mentally in my "unresolved" folder :-)

Regards,

Henning (HoHun)

[straffo]

Originally posted by Batz
that's the thread where I gathered most of the info in my post above.


look at duma quote in that thread



 

Maybe we need a new thread?

ouch I don't think so .... I should have  read slower

[Angus]

So the Gearing on the stick regarding elevators was as unfavourable as on the aileron side?
Somehow I'd presume that the exact gearing on the "pull" side would not be as acute, or rather depending on your position really. Tug-of-war vs. armwrestling really.
All makes you wonder.Must have something to do with airflow as well, and even C of G. I recall reading that the 109 had a tendency to nose down while building up speed in a steep dive.Some planes did not, some may have pitced up, and some would be over-responsive to aileron control at too high speed, giving the pilot the possibility to push the plane into disintegration at exessive speeds.
Anyway, still curious what the 109's stick forces were at some certain speeds

[MrCoffee]

Problem with the 109s elevator at high speeds was the force required on the control stick. If I  remember correctly, the value being at about 50 lbs at around 400 mph increasing. At higher speeds, you need less elavator movement. As the speeds drop down, more elevator movment is required. Someone had posted a graph a while back showing the stick force required on the 109(G10?) if I remember correctly. Shows the force at various speeds.

In AH, proper trimming helps greatly when flying the 109.

[GODO]

50lbs is a big force?? You can pull much than that with a single hand. 50Lbs may be a problem if you need to apply that force to the left or to the right, but pulling the stick with both hands? Even a child is able of that.

[MrCoffee]

50 lbs is not heavy but then it is substantial enough that repetative action could wear down the average pilot.

In regards to that graph, I remember looking at it and comparing it to the speeds I sometimes fight in AH and the stick forces in my 109 would have been 75-90 lbs for 400-480 mph range during dives etc... However at those speeds you dont need full elevator deflection.

[Kweassa]

I know Angus, but wanted to make people think a little more deeply.

 Make people think deeply?

 Or provocating Luft-enthusiasts to start hails of uproar?


 Just kiddin'

[MiloMorai]

Originally posted by Kweassa
Make people think deeply?

 Or provocating Luft-enthusiasts to start hails of uproar?


 Just kiddin'

Only one luft-enthusist or should that be fanatic, would start an uproar.

Just don't get him started on Flettner aileron tabs.

[GScholz]

Originally posted by MiloMorai
How effective can the elevator be if the pilot due to excessive force cannot readily make the elevator move?

Your attempt at intellectualism is noted. The 109 pilots that have mentioned high stick forces that I have read about say that they needed both hands to pull out of a steep dive, the elevator never "locked up". If the elevator was ineffective they could have pulled the stick to its limits and nothing would have happened. I believe AH limits stick forces to 40 or 50 lbs, which is incredibly weak considering the pilots are adults who easily could have pulled a lot more.

[GScholz]

To be fair I must say that the new 109G10 in AH2 beta seems to handle much better at high speed, so HTC or the new FM might have changed the characteristics of that plane a bit. However it is still beta so we won't know for sure until final release.

[GScholz]

In AH2 the 109G10 can pull blackout turns at a little over 500 mph without any trim change (combat trim is on) and I have partial control up to about 550 mph. Aileron control is much better at high speed than in AH1 which is nice indeed.

[VO101_Isegrim]

I had the opportunity to speak with a 109 veteran a few weeks ago about this question (109`s elevator/ailerons). I asked him wheter the controls were heavy at high speed, and he replied that yes, and described the elevators movement at high speeds as if the stick would be bolted into the floor. He could still move it, but he preferred the trimmer to help. Then I asked him about wheter this was the same with the ailerons, and he said that those, unlike the elevators were perfectly nice, there was no heaviness etc. He said it was like this at around 800 km/h.

It`s also interesting what the British found on a battered 109F they tested. It also seems to underline that the elevators were much heavier than the ailerons, yet despite the increase of control forces, the control surface`s effectiveness was still quite good:

" Manouveribility

No manouveribility trials were carried out against other aircraft but the Me.109F was dived up to 420 mph IAS, with controls trimmed for level flight, and it was found that altough the elevators had become heavy and the ailerons stiffened up appreciably, fairly tight turns were still possible. "

[Angus]

That would be any 109 after 109E right?