109 engine load vibration

[TomcatViP]

OK boys, let me clarify some points here as I see the same error repeated over and over on the forum.

In the 1930's, the plane came from aerodynamics limitation in their race for speed to refined monoplane configuration only limited by their engine's power.

A pilot trained in the 30's was used to deep it's nose to get some airspeed since the available power cld hardly coped with the high drag of the airplane (despite three time the power the bi-planes hardly gained 50% in speed btw 1920 and 1935).

Nowadays, a fighter pilot just slam the throttle and race toward his maximum airplane's Mach as the aerodynamics is much more refined than in the 40's. He will even raise the airplane nose to reach less denser air to increase it's speed !

During the war, most pilot use to dive slightly to get to the max speed available on their type. Just slamming the throttle forward could prove so lengthy that the engine cooling system would hve difficulties reaching it perfectly level (especially in the middle of a mission deep into enemy territory)

Pls view the max speed as the max sustainable speed at level flight (the point at your IAS indicator were the needle will fully stabilize itself after a slight dive). It's way more difficult otherwise. And feel yourself lucky we still not hve any gust model !

Yeah old Il2 FM was ridiculous for some of the planes on that point. Oh and I didn't mention the "refined" model of some of the Mod patch highly promoted here and there

[41Sqn_Banks]

Isn't the maximum level speed shortly after a dive the same as after a acceleration by engine power alone? Once the acceleration induced by the dive is gone the drag will decelerate the aircraft to the same speed.
Of course it will take time to accelerate by engine power and it will take time to decelerate once the dive ended, but luckily we can disable the heat effect and fly unlimited at full power to do the speed tests.

[TomcatViP]

yes it is

[phoenix1963]

Originally Posted by TomcatViP

OK boys, let me clarify some points here as I see the same error repeated over and over on the forum.

In the 1930's, the plane came from aerodynamics limitation in their race for speed to refined monoplane configuration only limited by their engine's power.

No, top speed in level flight is ALWAYS limited to the point where engine power (and efficiency in getting that power into actual thrust) matches drag, no matter how old the aircraft is.

Originally Posted by TomcatViP

A pilot trained in the 30's was used to deep it's nose to get some airspeed since the available power cld hardly coped with the high drag of the airplane (despite three time the power the bi-planes hardly gained 50% in speed btw 1920 and 1935).

Nowadays, a fighter pilot just slam the throttle and race toward his maximum airplane's Mach as the aerodynamics is much more refined than in the 40's. He will even raise the airplane nose to reach less denser air to increase it's speed !

No, the modern fighter pilot has less to gain by dipping the nose because the power-to-weight ratio is so much higher now.

Originally Posted by TomcatViP

During the war, most pilot use to dive slightly to get to the max speed available on their type. Just slamming the throttle forward could prove so lengthy that the engine cooling system would hve difficulties reaching it perfectly level (especially in the middle of a mission deep into enemy territory)

No, any pursuer could slightly dive as well, but it would be an advantage for the aircraft with less increase in drag with speed.

Originally Posted by TomcatVIP

Pls view the max speed as the max sustainable speed at level flight (the point at your IAS indicator were the needle will fully stabilize itself after a slight dive). It's way more difficult otherwise. And feel yourself lucky we still not hve any gust model !

Diving is simply a convenient way of speeding up.

Nothing personal Tomcat, but either you need to read-up about aerodynamics, or you are trolling.

56RAF_phoenix

[TomcatViP]

Originally Posted by phoenix1963

No, top speed in level flight is ALWAYS limited to the point where engine power (and efficiency in getting that power into actual thrust) matches drag, no matter how old the aircraft is.



No, the modern fighter pilot has less to gain by dipping the nose because the power-to-weight ratio is so much higher now.



No, any pursuer could slightly dive as well, but it would be an advantage for the aircraft with less increase in drag with speed.



Diving is simply a convenient way of speeding up.

Nothing personal Tomcat, but either you need to read-up about aerodynamics, or you are trolling.

56RAF_phoenix

It might be tht you are reading me trought some critism enhancer lens.

1st no : of course didn't say either... it's just way more simple to let the nose drop down : do the math (thrust to weight approx 0.2+ and 1-cos 30=0.2-)

2nd no : if you are going trought transonic flight it's way much easier to do it at alt.

3rd no : I wasn't discussing tht case. But you are true. We hve alrdy discussed tht point elsewhere do I guess right ?

Your conclusion coroborate what I am only saying : it's way more simle to deep the nose than to fight the ctrls and your eng para in a long flat run to max speed.

For the biplan exemple: you can put a wright cyclone on a Spad XIII it won't go much faster... How wait ... the Russians did it in the An2

So as I said we went from drag limitted plane to Eng pow limmitted monoplanes. But of course it's a comparaison. You don't hve to take me by the word saying tht I declare the monoplanes to be drag free!

[phoenix1963]

I think the underlying point you are trying to make is that the ratio of drag to lift was sharply reduced when monoplanes were introduced. I suspect we can agree on that.

I do find it interesting that the Italian plane designs seem to have got stuck in the early 1930s, British designs got stuck in about 1942, German designs continued to get better, but they couldn't deliver them, while early US designs were BAD but late war ones excellent.

Each country peaked at different times.

A wild generalisation, but interesting.

56RAF_phoenix