Best Fighter III

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50% of people make up half the population
73.53% of all percentages are made up on the spot
 
Hop,

You do realize that the 109E had approximately 5-10 min worth of fuel to play around with once it reached London, right ? And this is without having engaged in combat even once.

The reason the LW lost the BoB is like nearly everyone here has been trying to tell you - the 109E's lack of range and Göring's silly change of tactics.
 
The reason the RAF won the Battle of Britain was that they shot down more planes than they lost and they could replace their losses. Losses of pilots put the Luftwaffe in an even worse position.
 
...true. But did it helped them tactically? The RAF losses over France in 1941-42 were extremely high in comparison to the Luftwaffe losses there. So, I conclude that the RAF Spits Hurr. shared the same problems in retrospect.
By the way, 40% of the Jaflieg were E-1 but how many of the RAF were Spitfires? You know the answer.
 
The percentage of E-1 was only to show us that 40% of the Luftwaffe's fighter force over Britain had half the firepower of the Spitfire or Hurricane.

There's countless reasons why Battle of Britain turned out the way it did. I've always heard that the Bf-109 had 20 minutes loiter over London.
 
I've always heard 20 minutes over London. Care to provide anything to the contrary?
 
Well 5-10 min is what I've been hearing from vets through the years, and its also pretty consistent in books about it - And the Emil's range certainly seems to suggest it as-well..

The Emil has 95min of endurance at 2/3's rated power (Cruise setting), and it takes approx. 45min to get to London from the French coast at the Emil's cruising speed - 400 kph.
 
The Emil has 95min of endurance at 2/3's rated power (Cruise setting), and it takes approx. 45min to get to London from the French coast at the Emil's cruising speed - 400 kph

Cruising speed at 2/3 power would be well above 400 km/h.

Max speed on the Emil was about 570 km/h. 2/3 speed would equal 375 km/h, and speed is not linear with power.

2/3 power should give about 470 km/h in the Emil, by my "very rough) calculations.

Central London is about 135 km from the French coast, at a fast cruise of 470 km/h that would take about 17 mins

20 minutes combat would use about 100 litres.

If you use 100 litres in combat, 100 litres to warmup, takeoff, climb to altitude and reserve, that gives you 200 litres left, or half your endurance time, to cruise to and from target. So, about 22 minutes cruise endurance each way, which still allows 20 minutes combat over central London, with some extra reserves (for example climbing to height after combat is over for the cruise home). (20 minutes combat is what USAAF fighters assumed in their flight planning)

It certainly didn't allow the Luftwaffe to go much north of London, and if the RAF had pulled their fighters north of London it would have put the Luftwaffe in a very awkward position, but as the RAF remained in the SE, the 109 had the range to engage them effectively. Whilst fuel was a bit tight over London, for most of the battle over Kent and the channel, fuel wasn't really an issue at all.
 
Hop,

The Bf-109E has a cruising speed of 400 kph, which is achieved at 2/3's rated power.

London is approx. 200 km from the French coast - ~40-45min's taking climb to altitude into consideration.
 
Anyway you look at it, its still not much endurance.

I maintain that if the -109's had more endurance, they could have had longer escort times for the bombers and wouldnt have to break off contact(s) so soon to return back to base. The RAF loss's would have increased.
 
Are there instances of Bf 109s breaking for home before the bombers?

Most of the targets being bombed were much closer to France than London. Tangmere, Biggin Hill and other airfields in 11 group being only a couple of miles from the coast.

Even so the RAF could have just fell back to 10 and 12 group and actually fought over SE England.

The Es speed at 2/3 throttle (740hp) is ~500kph not 400kph. The relationship between power and Vmax is cubed.
 
London is approx. 200 km from the French coast

London is a good deal closer than that, particulary the SE of London, which is what the Luftwaffe was mostly bombing.

Here's a map showing a 200 km radius from the Pas de Calais (about 12 km inland, ie the line would be 12 km further into England if taken from the coast)

878_1152310143_200kmradius.jpg


Notice it goes way beyond even NW London. It's actualy 52 km beyond docklands in London, and 12 km back from the coast, so coast to docklands should be 136 km from the French coast.

The Bf-109E has a cruising speed of 400 kph, which is achieved at 2/3's rated power.
I can't understand that claim.

Drag, and thus power required, goes up with the square of speed, ie double the speed requires 4 times the power. If Bf 109E max speed was about 570 km/h, which I believe it was, then 2/3 power should give a cruising speed of about 465 km/h (I've recalculated)

465 km/h * 1.225 = 570 km/h

If power = 1000 (units unimportant) then 2/3 power = 666

666 * 1.225 * 1.225 = 999 power

In other words, if the drag goes up with the square of speed, which it does, the Emil should cruise at 465 km/h at 2/3 power if speed at maximum power = 570 km/h
 
Bloody ****, measured from the wrong beachhead, sorry about that Hop :oops:

However about that map Hop, are you sure you have measured that correctly ? I used google's map, and measured the distance as ~160km from Dunkerque. Google Maps

I guess that would leave fuel for about ~5-10min of 'combat' over London before having to go home, not nearly enough time to prove an effective protection for the bombers however. And had the bombers already once been intercepted before London, then the 109 fighters would already be leaving for home once London was reached. And indeed allot of LW fighters got bagged whilst running for home - both German and British vets testify to that.

And about the Emil's cruising speed, well 400 kph is what nearly every one of my sources quote, some others even have it as 375 kph...
 
Cruising speed might be 400kph, well it probably is, it just isn't achieved at 2/3rds power.

Hop, The relationship between power and speed is cubed for the large proportion of the flight envelope. Lots of details here and here if you are interested.
 
Hop said:
London is a good deal closer than that, particulary the SE of London, which is what the Luftwaffe was mostly bombing.

Here's a map showing a 200 km radius from the Pas de Calais (about 12 km inland, ie the line would be 12 km further into England if taken from the coast)

878_1152310143_200kmradius.jpg


Notice it goes way beyond even NW London. It's actualy 52 km beyond docklands in London, and 12 km back from the coast, so coast to docklands should be 136 km from the French coast.


I can't understand that claim.

Drag, and thus power required, goes up with the square of speed, ie double the speed requires 4 times the power. If Bf 109E max speed was about 570 km/h, which I believe it was, then 2/3 power should give a cruising speed of about 465 km/h (I've recalculated)

465 km/h * 1.225 = 570 km/h

If power = 1000 (units unimportant) then 2/3 power = 666

666 * 1.225 * 1.225 = 999 power

In other words, if the drag goes up with the square of speed, which it does, the Emil should cruise at 465 km/h at 2/3 power if speed at maximum power = 570 km/h

I didn't check out the math but your logic is correct. I suspect that, if indeed 400 km/h was stated as 2/3 power it was probably some sort of power setting (rpm, manifold pressure, throttle angle, etc.) which did not reflect linearly with engine power output. Or it could just be an error.
 
The power output of any piston engine is a curve. That curve is optimized to place max power at the point where it is most usefull. 2/3 throttle may represent 40% power while 85% throttle may be 90% power these examples are dependant on cam/ignition timing, boost, type of boost, fuel, and the designated use the combination is set up for. Throttle/Power is only linear in jet engines and then only after a certain power output is reached (maybe Flyboy can enlighten us on that score)

wmaxt
 
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