Beating a Dead Sea Mammal: How can a non-ASB Operation Sea Lion thread be created?

A slightly delayed response to the statement that the RN wouldn't put capital ships in the Channel. IOTL, HMS Revenge was at Portsmouth in September 1940 and crossed the Channel to bombard Cherbourg in October 1940 as part of Operation Medium. Plus the monitor HMS Erebus bombarded Calais harbor at the end of September 1940. The RN wasn't thinking the English Channel was unsuitable for capital ships by any means.
yes it was, it was only willing to risk its oldest and most useless battleships there, and even then, only at night; the monitors sometimes had to be towed into action while the Revenge had a very short life afterwards (and was referred to by Churchill as a "coffin ship"). You forgot to mention the other battleship in Portsmouth- the Centurion, which was a target ship without any guns. Anyway the RN had to be prodded to move the Revenge south and it didn't arrive until a month after the original planned invasion date. If it had moved within range of the channel guns I'm sure it would have provided a splendid, relatively slow-moving target, though maybe it would not have to be moved as some of the beaches were in range of its guns while it was in port - I'm not sure. Also Operation Medium occurred in the broader and deeper reaches at the centre of the Channel, with lots of room to move close by, further west. The Stukas had effectively closed the dover gap in July 1940 when the Royal Navy cancelled the convoys and forbid ships from operating there during daytime.
 

Ian_W

Banned
yes it was, it was only willing to risk its oldest and most useless battleships there, and even then, only at night.

What the RN is willing to do under normal circumstances, and what it is willing to do to defeat a German invasion are two different things.

Do you really think Churchill is unwilling to fire Admirals until he finds one who is willing to fight ?

At the end of the day, if the invasion is defeated and the RN loses half the Home Fleet's battlewagons, that is still a massive win for the British.
 
What the RN is willing to do under normal circumstances, and what it is willing to do to defeat a German invasion are two different things.

Do you really think Churchill is unwilling to fire Admirals until he finds one who is willing to fight ?

At the end of the day, if the invasion is defeated and the RN loses half the Home Fleet's battlewagons, that is still a massive win for the British.
Nobody said the RN was unwilling to fight, just that it wasn't going to risk its capital ships where they weren't needed - it was going to use the masses of smaller ships available instead, which were better suited to the task. Meanwhile the capital ships were needed to secure the Atlantic sea lanes. The RN said it would risk its capital ships in the Channel only if the Germans did likewise. But both Forbes and Pound said this and the Chiefs of Staff and Churchill allowed it, instead of sacking them. Actually if the RN loses too many ships then it has lost, 40 destroyers being the margin between losing and surviving the Battle of the Atlantic for instance.
 

hipper

Banned
yes it was, it was only willing to risk its oldest and most useless battleships there, and even then, only at night; the monitors sometimes had to be towed into action while the Revenge had a very short life afterwards (and was referred to by Churchill as a "coffin ship"). You forgot to mention the other battleship in Portsmouth- the Centurion, which was a target ship without any guns. Anyway the RN had to be prodded to move the Revenge south and it didn't arrive until a month after the original planned invasion date. If it had moved within range of the channel guns I'm sure it would have provided a splendid, relatively slow-moving target, though maybe it would not have to be moved as some of the beaches were in range of its guns while it was in port - I'm not sure. Also Operation Medium occurred in the broader and deeper reaches at the centre of the Channel, with lots of room to move close by, further west. The Stukas had effectively closed the dover gap in July 1940 when the Royal Navy cancelled the convoys and forbid ships from operating there during daytime.


You know very little of HMS Revenges operations in the Channel, Revenge arrived in mid September and happily operated within close range of german Naval Guns

From Naval history.net
September 14th - REVENGE and cruiser EMERALD sailed from the Clyde for Plymouth to come under the command of Western Approaches, escorted by destroyers MACKAY and WESTCOTT.
En route MACKAY and WESTCOTT detached and destroyers SCIMITAR and SKATE joined.
(This deployment was made by the Admiralty when intelligence suggested that a large scale invasion appeared imminent. Had the invasion taken place REVENGE would have been the only capital ship in the Channel area)
15th – REVENGE, EMERALD, MACKAY and WESTCOTT arrived at Plymouth.

October 11th – At 0035 hours the REVENGE force RVed with MGB’s 40, 42, 43, 44, 45, 46 and 51 who had sailed from Weymouth and were tasked with covering the bombarding force from E-Boats.
At 0230 hours the MGB’s formed a screen ahead of the REVENGE force ready to engage any E-Boats or small vessels encountered.
At 0315 hours the bombing attacks commenced ad flares were dropped over Cap de la Hague to enable REVENGE to obtain an accurate fix.
From 0333 to 0351 hours from a range of approximately 15700 yards the REVENGE group bombarded Cherbourg harbour. During the 18 minute bombardment 120 x 15in shells were fired by REVENGE and a total of 801 x 4.7in shells from her escorting destroyers.
The force then retired under fire from a German shore battery, estimated as up to 13.5in calibre, east of Cherbourg. The firing continued for 30 minutes and although accurate no hits were achieved. During the withdrawal REVENGE worked up to 21½ knots.
 
At the end of the day, if the invasion is defeated and the RN loses half the Home Fleet's battlewagons, that is still a massive win for the British.

I am not so sure on this last point which is why I think a failed Sea Lion discussion might yield far more of a substance to noise ratio than all the countless Sea Lion Success threads.

However the main issue for the RN battle and battlecruiser squadrons per Sea Lion was that there was very little for them to fight. Cruisers with their 8" or 6" main battery and 4" secondaries can equally dominate destroyers and sink barges and are individually far more expendable. Given the paucity of German means of Naval resistance the destroyer force and lighter units could probably do the job, aided by elements of the cruiser force they certainly could.
 

Ian_W

Banned
I am not so sure on this last point which is why I think a failed Sea Lion discussion might yield far more of a substance to noise ratio than all the countless Sea Lion Success threads.

However the main issue for the RN battle and battlecruiser squadrons per Sea Lion was that there was very little for them to fight. Cruisers with their 8" or 6" main battery and 4" secondaries can equally dominate destroyers and sink barges and are individually far more expendable. Given the paucity of German means of Naval resistance the destroyer force and lighter units could probably do the job, aided by elements of the cruiser force they certainly could.

Well, given the paucity of the German Navy post-Norway, there is very little for any of them to fight.

Cruisers are also more vulnerable to dive bombers ... what Im thinking of is a Revenge-plus strategy, where a couple more older and more obsolete battleships go into the channel - if the main effort of the Luftwaffe becomes hunting them, then they get distracted from going after the RAF or Army.

Basically, I don't think the Luftwaffe can resist a battlewagon, and without the kind of specialised training that they dont have (and can't get without the RN noticing) they wont be very good at sinking them.
 
410 mrge /3.88 mpm = 105.7 minutes aloft.

Rule of thirds.

410/3= 136 miles.

Cruise time loiter at 136 miles with no fuel reserve cushion at all: 35.3 minutes at 3.88 mpm (Buzzard bait condition; 233 mph at 22,965 ft. Slow at medium altitude means dead.)

Combat time with no fuel reserve at 136 miles from base with no fuel reserve cushion at all (highly theoretical) 17.65 minutes at 5.8 mpm. (still Buzzard bait condition of 348 mph at 14,565 ft as the Spitfires can bounce from above.)

Those are the numbers crunched at best conditions for best BoB BF 109E type in service. And that is why the BF 109 is not going to be 20 minutes north of the Thames unless the LW pilot has no RTB fuel or has a death wish.

Average cruise speed for the Bf109 was actually somewhere in the region of 4.5 miles per minute (max cruise speed is more like 5 miles per minute). 90 minutes = 405 miles (stated as 410 miles in most sources). And no that does not suggest a reach of 205 miles and that is not what I’m suggesting either.

The rule of thirds as far as I’m aware relates to fuel consumption rather than endurance, you use a third of your fuel for the journey to target, allow a third for possible combat and the final third for the return journey. This is after you’ve made a 20-25% allowance for take-off and landing. So following your logic of dividing the max range by 3 one would exclaim 137 miles! But that’s not how it works. So the actual time allowances are more like, at maximum range of 125 miles, 20 minutes for take-off and landing, 60 minutes to travel to and from target and 10 minutes for possible combat. Remember most combats were over and done with within 5 minutes as ammunition was the deciding factor in the length of a fight.

At least now we are using the same data, 410 miles max range and 136 miles using the rule of thirds (or 137 depending on whether you round up or down).

Where we do differ, and probably why you’re calling my calculations into question, is that you are measuring endurance in terms of time whereas I’m trying to work things out based on fuel consumption. The way I see it is that with a target at say 100 miles there is just too much difference in time between an escort mission at 190 mph and a free sweep mission at 300 mph for there to be any consistency in time aloft; 32 minutes as opposed to 20 minutes. Basically your calculations are based on miles per minute, mine on miles per gallon. That’s not to say either method is wrong, just that we have different views on what is important. For example endurance expressed in terms of time for a Mustang escorting bombers to the heart of Germany is definitely the right thing to do but in this instance you can’t expect the rule of thirds to apply. Each situation is different.

So to lay it out in terms of detailed calculations as you have (and there’s a lot of assumptions on my part as I’m no expert in this kind of thing, I’m sure there could be others better able to correct me) here’s what I have.

Fuel carried = 88 Imperial Gallons

Fuel split = 25% for take-off (Cajus Becker puts this figure at 20% but for ease of calculations I’ve assumed 25%), then the rest is split into thirds for outbound, combat and inbound. So there are four phases each consuming 22 Gallons.

Max range = 125 miles (Alfred Price)

Average time in the air = 90 minutes (Len Deighton)

Average speed = 273 mph (410 miles / 90 minutes x 60)

Therefore my assumption is:

Miles per gallon at 273 mph (77% of max) = 125 / 22 (range / fuel allocated) = 5.68 mpg

Note: Mpg if you use 20% fuel for take-off as per Cajus Becker drops to 5.33

110 miles to Duxford at 273 mph would use 22 Gallons for take-off and 38.73 Gallons for outbound and inbound combined, leaving 27.27 Gallons for combat (Approx 31% of fuel). If take-off uses 20% rather than 25% this works out at 17.6 take-off 41.3 for journey and 29.1 for combat (Approx 33% of fuel).
 

SsgtC

Banned
110 miles to Duxford at 273 mph would use 22 Gallons for take-off and 38.73 Gallons for outbound and inbound combined, leaving 27.27 Gallons for combat (Approx 31% of fuel). If take-off uses 20% rather than 25% this works out at 17.6 take-off 41.3 for journey and 29.1 for combat (Approx 33% of fuel).
I think I see where you're going wrong here. You're assuming cruise speed all the way to Duxford with no RAF intercept until directly over the target. The RAF would have intercepted long before then, forcing the escorting 109s into combat long before they reach their theoretical max combat radius. The only way the 109s can escort a strike that far is to have multiple squadrons assigned to the same bomb group, with successive squadrons declining combat with the RAF until certain points in their transit. But that's not really possible without having something close to air supremacy. Which the Germans did not have. At best, they had air parity for a brief time. And in that situation, what good are fighter escorts if they refuse to fight? You might as well send your strike in unescorted at that point.
 
I think I see where you're going wrong here. You're assuming cruise speed all the way to Duxford with no RAF intercept until directly over the target. The RAF would have intercepted long before then, forcing the escorting 109s into combat long before they reach their theoretical max combat radius. The only way the 109s can escort a strike that far is to have multiple squadrons assigned to the same bomb group, with successive squadrons declining combat with the RAF until certain points in their transit. But that's not really possible without having something close to air supremacy. Which the Germans did not have. At best, they had air parity for a brief time. And in that situation, what good are fighter escorts if they refuse to fight? You might as well send your strike in unescorted at that point.

Yes I agree but this is why I posted this a couple of pages ago…

“Okay so that’s ideal conditions, no combat involved which is highly, highly unlikely. Most likely there will be a combat phase somewhere around the Thames Estuary, if this is a heavy attack it could result in the whole formation turning right round and heading for home, no problems with fuel. If it is a light attack the close escorts job is to stay with the bombers and let the top cover deal with the threat, some of which may have to run for home after running out of bullets or receiving damage. Still no worries about fuel. Now in all likelihood there is a running battle to the target so more and more fighters are having to peel off mostly due to ammunition but possibly because of fuel the closer they get to the target. But this is why they increased the escort to the point where there three times as many escorts as bombers and why the Germans sent out further fighters to cover the final part of the withdrawal.”

But what you have to remember is where this conversation began, how far Fighter Command would retreat with the answer outside the range of the Bf109 which in my view would have to be north of Duxford. In this scenario the Luftwaffe would have air superiority.
 
Time is the ONLY criteria. This is why your assumptions are wrong from the start. No pilot can be sure what he will do in a flight. He keeps a fuel reserve measured in minutes of flight at cruise as his safety cushion. It is true even in combat. That is why an F4F-3 with a book range of roughly TWICE the standard BF109 E-3 only had an effective radius from base of maybe 40 nautical miles additional from its home base carrier over the Emil under its ideal flight conditions during the BoB. Get used to thinking in terms of time aloft at variable speeds and altitudes, not miles flown straight and level at best cruise at best altitude one way on a tank of gas. Who knows if the engine is even metered to fuel flow at best rate? Maybe the mechanic was drunk and/or hungover when he serviced the plane. THAT is 10 minutes gone right there in a DB 601, if the mechanic screws up the fuel flow to the injectors.
 

hipper

Banned
Time is the ONLY criteria. This is why your assumptions are wrong from the start. No pilot can be sure what he will do in a flight. He keeps a fuel reserve measured in minutes of flight at cruise as his safety cushion. It is true even in combat. That is why an F4F-3 with a book range of roughly TWICE the standard BF109 E-3 only had an effective radius from base of maybe 40 nautical miles additional from its home base carrier over the Emil under its ideal flight conditions during the BoB. Get used to thinking in terms of time aloft at variable speeds and altitudes, not miles flown straight and level at best cruise at best altitude one way on a tank of gas. Who knows if the engine is even metered to fuel flow at best rate? Maybe the mechanic was drunk and/or hungover when he serviced the plane. THAT is 10 minutes gone right there in a DB 601, if the mechanic screws up the fuel flow to the injectors.


Ian & McP perhaps you could just look up the furthest north point reached by 109s during the BOB and agree that’s the maximum range according to the LUftwaffe ?

But interesting thread.

NB if you look at the effects of the Jetstram on LW flights to London you might think That time is more important than range. I think Dr Price has comments on the jetstream in ne of his books
 
Actually if the RN loses too many ships then it has lost, 40 destroyers being the margin between losing and surviving the Battle of the Atlantic for instance.

However, since the Germans planned to use pretty well all their U-boats, it's likely that they'll have almost none left to take advantage of a temporary reduction in the number of available escorts - and in any event I expect that the actual number of losses will be much closer to 4 than 40...

During the withdrawal REVENGE worked up to 21½ knots.

That's interesting as you'll often see claims that the R's were only good for 19 knots at best, but if Revenge - the ship in worst condition - can do 21.5 knots then the others are likely to be at least a bit faster.
 

SsgtC

Banned
Ian & McP perhaps you could just look up the furthest north point reached by 109s during the BOB and agree that’s the maximum range according to the LUftwaffe
Not really. Because it's very likely that the farthest North they flew was essentially one waying it. If a pilot is injured and doesn't think he can made it back to base, he may very well ignore his fuel state and stay and fight it even pursue well beyond his max combat range.
 
Ian & McP perhaps you could just look up the furthest north point reached by 109s during the BOB and agree that’s the maximum range according to the LUftwaffe ?

But interesting thread.

NB if you look at the effects of the Jetstram on LW flights to London you might think That time is more important than range. I think Dr Price has comments on the jetstream in ne of his books
I think the best evidence is that escorted raids were regularly sent to Portsmouth and Southampton from bases in Normandy in the region of Caen... 100-130 miles away.

Debden was attacked several times with escorting 109s and that is only 10 miles south of Duxford. Only one raid is recorded for Duxford but it was turned back before it got there by heavy resistance.
 
If time is the only criteria how come the fuel guage in the Bf109 has graduations for litres of fuel rather than minutes?

Why train pilots on fuel rate flow?
If you LOOK at pilot training manuals, this is standard information for type of plane. Gallons or liters as the measurement unit, the pilot, as part of his fuel management, has to know flow rates in liters or gallons per minutes: at cruise, at full, at over-boost (variously called war-emergency or military power) and know the crucial flow differences at the various altitude bands, if he was a WALLIE or the different auto flow settings if he was a German. This is an essential (as in a matter of life and death) part of pilot training. The fuel gauges whether by weight gauge (spring) or volume (dipstick) gave an approximate measurement of amount of fuel available. Most car drivers never think of it, because their fuel gauge is fractionated in quarters and if they run out of gas they walk, but a pilot has to KNOW within 10% about how much fuel he has onboard for time of use. (There are also plane trim issues as tanks empty, but here we are discussing time aloft and how it is measured.)
 
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