B17 v Lanc bomb load

[chiglet]

One of my [retired] colleagues was a Lancaster rear gunner. I made a model of "his" Lanc for him. Bog standard Lanc. Nose turret, mid upper NO ventral turret [as NOT "standard fit"] but with a Rose-Rice twin .50cal tail turret. I also made a model Lanc for my retiring Boss. Bags pf photos, bags of "First hand Gen"...His had the blisters on the cockpit sides, his mate didn't.
I was also very fortunate to be shown around S for Sugar, on the gate at RAF Waddington. I was in "shirt sleeved dress" and it was not an easy aeroplane to enter and exit... my hat goes off to those young [and some not so young] men who nightly flew on missions against the Enemy

[45-Shooter]

First off, do yourself a favour and ditch Wikipedia, as pretty much anybody can edit it. Next get yourself a copy of the Lancaster drawings (internet or ask the people at Avro Heritage nicely), and get a few decent books on the aircraft. I can recommend those by Francis K Mason, Bruce Robertson, and Harry Holmes as excellent reading.

I agree and have been there in person half a dozen times. Never wanted to spend the money on the factory drawings when so many planes were modified in the field.

Referring again to your previous post -

1. You missed the point entirely regarding bombloads. Your statement "All other bombs were carried by specially modified planes WO bomb bay doors." is incorrect, No it is not and I did not make the original statement! and the link I posted to shows this. No it does not and in fact the bottom or next to bottom picture prooves my point with a clearly modified plane! I'm not debating where the individual shackles are in the Lancaster or the B17, just the variance of load each can carry. I agree completely!

2. The availablility difference is my point, which again you missed.. The fact that the B17 was available in higher numbers at any one time means of course the type is going to drop more tonnage. No, it is you that missed the point! The B-17 was never available in greater numbers in England than the Lancaster! Ever! The larger numbers of B-17s were spread in to four theaters of opps! Match numbers of aircraft over a matched period of time. There were more Lancs available at any given time in England! They were available and in service in larger numbers and sooner than the B-17. Those are facts that you can not honestly dispute.

3. Please provide the figures you have from the pilots notes, or from the manufacturer maybe, that show operating the Lancaster at its service ceiling would cut the payload by more than half. The statement you make on this is your opinion, and nothing more. No, it is a fact. The more any aircraft weighs, the lower it must fly with any given thrust, wing area and L/D.

What isn't opinion is that a standard Lancaster could and did carry a substantial payload over an excessively long range Yes, I agree! - the 9 Sqn and 617 Sqn aircraft that attacked the Tirpitz weren't the 'Special' aircraft. Wrong again! This is not opinion, and regardless of number of aircraft used it was done operationally; so we can take this as a measure of what a a fairly standard aircraft is capable of. Wrong again! They were "Special" aircraft. See the quote from the link you posted below! Exactly how many Lancs had the special bulged bomb bay doors and higher rated engines?

Area Bombing Raids (Blast and Demolition)

Bomber Command Executive Codeword: "TALLBOY"

Target Type: Submarine Pens, Battleship Tirpitz.
1 x 12,000 lb deep penetration, spin-stabilised bomb containing approx. 5,760 lb of Torpex D. Usually with trip-fused 0.01 sec delay. Carried by Lancaster's with bulged bomb doors. Raids On Exceptionally Strong Structures.

The ineffectiveness of the vast majority of the strikes launched by the Fleet Air Arm in mid-1944 led to the task of Tirpitz's destruction being transferred to the RAF's No. 5 Group. The RAF used Lancaster bombers to carry 6-short-ton (5.4 t) Tallboy bombs to penetrate the ship's heavy armour.[59] The first attack, Operation Paravane, took place on 15 September 1944; operating from a forward base at Yagodnik in Russia, 23 Lancasters (17 each carrying one Tallboy and six each carrying twelve JW mines), scored a single hit on the ship's bow.[50]

The RAF made a second attempt on 29 October, after the ship was moored off Håkøy Island outside Tromsø. Thirty-two Lancasters attacked the ship with Tallboys during Operation Obviate.[50] As on Operation Paravane, No. 9 Squadron and No. 617 Squadron carried out the attack together, which resulted in only one near miss,[60]

Operation Catechism, the final British attack on Tirpitz, took place on 12 November 1944.[50] The ship again used her 38 cm guns against the bombers, which approached the battleship at 09:35; Tirpitz's main guns forced the bombers to temporarily disperse, but could not break up the attack.[63] A force of 32 Lancasters from Nos. 9 and 617 Squadrons dropped 29 Tallboys on the ship, with two direct hits and one near miss.[50]
4. Engines - Lancaster BVI Merlin 85 1635hp Exactly how many Lancs were fitted with these engines? Exactly how many had standard Mark XX Merlins?

B VI Nine aircraft converted from B IIIs. Fitted with Merlin 85/87 which had two-stage superchargers, giving much improved high altitude performance. The B VI could achieve a maximum speed of 313 mph (505 km/h) at 18200 ft (5547 m) at 65,000 lb (29,484 kg) take off weight and a service ceiling of 28500 ft (8687 m) at the same weight; climb to 28000 ft (8534 m) at 65,000 lb (29,484 kg) take off weight was accomplished in 44.8 minutes with a maximum climb rate of 1080 fpm (5.5 m/s)at 1000 ft (305 m).[30] A Lancaster B VI was dived to a maximum indicated speed of 350 mph (565 km/h), or Mach 0.72 at 25000 ft (7620 m) in June 1944.[31] The Merlin 85/87 series engines were fitted with annular cowlings similar to the post war Avro Lincoln and three bladed paddle-type propellers were fitted. These aircraft were only used by Pathfinder units; by No. 7 Squadron RAF, No. 83 Squadron RAF, No. 405 Squadron RCAF and by No. 635 Squadron RAF. Often used as a "Master Bomber" the B VI's allocated to RAF Bomber Command (2 being retained by Rolls Royce for installation and flight testing)[32] had their dorsal and nose turrets removed and faired-over. The more powerful engines proved troublesome in service and were disliked by ground maintenance staff for their rough running and propensity to 'surge and hunt', making synchronisation impossible. This 'hunting' is caused by variations in the fuel/air mixture and could over time eventually damage the engine.[33] The B VI was withdrawn from service in November 1944.
Two speed, two stage.Exactly how many Lancs were fitted with these engines during the war? Exactly how many had standard Mark XX Merlins during the war? Later used in the Lancaster IV, also known as the Lincoln. These planes are not Lancasters, they are Lincolns! Do I really have to do all your homework for you just because wikipedia is lacking? Do you really have to use limited production and modified aircraft to prove your point? Please list production numbers of each type by engine!

5. There are more than 15 points, depending on which carriers are fitted. Please show me the 12 point version of a Lanc bomb bay, as I can only find the Manchester version which shows 8 points, for 1,000lb bombs, later with the provision for the 4,000lb bomb. You could be refering to the first batch of Lancasters which used Manchester fuselages maybe? Does it matter? which version of the planes we are talking about, if they made less than say 100 of them? How about limiting the discussion to versions which were made in numbers exceeding 100 each! B Mk-I, B Mk-II, B Mk-III and B Mk-X. About 1/3 of B Mk-Is had bulged bomb bay doors. Many of these planes had top and sometimes nose turrets removed. A few of the late B Mk-Is had the two stage/two speed blowers. Whether they actually made more than 100 of them with these engines during the war is debated. Post war refits do not count. Late War planes that did not see service because of fitting out delays do not count.

It is generally accepted that at the beginning of the war, accuracy was poor. By the end of the war the concept had been refined so well that the destruction of certain cities is still hotly debated today.

7. Glad we agree on something...

"The Lanc's engines were single stage, two speed blowered, WO Turbo-charger! While it was simple, there is no way to compaire it to the Supercharged with turbo-blower used in the American planes."

Explain please? The Merlin engine, and its Griffon engine counterpart lasted in frontline service with several air forces far longer than the B17's efforts. What does this have to do with anything? We replaced them with jets, just as soon as we could. They were also pretty much self contained, Not in dispute. Lancasters didn't have a habit of blowing their wings apart when the turbosuperchargers got annoyed either. Neither did B-17s, which did not blow up or burn nearly as often as Lancs. Quote;
SuperchargerCentral to the success of the Merlin was the supercharger. A.C. Lovesey, an engineer who was a key figure in the design of the Merlin, delivered a lecture on the development of the Merlin in 1946; in this extract he explained the importance of the supercharger:

"Coming now to specific development items we can ... divide them into three general classes:

1. Improvement of the supercharger.
2. Improved fuels.
3. Development of mechanical features to take care of the improvements afforded by (1) and (2).

Dealing with (1) it can be said that the supercharger determines the capacity, or ... the output, of the engine. The impression still prevails that the static capacity known as the swept volume is the basis of comparison of the possible power output for different types of engine, but this is not the case because the output of the engine depends solely on the mass of air it can be made to consume efficiently, and in this respect the supercharger plays the most important role ... the engine has to be capable of dealing with the greater mass flows with respect to cooling, freedom from detonation and capable of withstanding high gas and inertia loads ... During the course of research and development on superchargers it became apparent to us that any further increase in the altitude performance of the Merlin engine necessitated the employment of a two-stage supercharger."[26]

As the Merlin evolved so too did the supercharger; the latter fitting into three broad categories:[27]

1. Single-stage, single-speed gearbox: Merlin I to III, XII, 30, 40, and 50 series (1937–1942).[nb 3]
2. Single-stage, two-speed gearbox: experimental Merlin X (1938), production Merlin XX (1940–1945).
3. Two-stage, two-speed gearbox with intercooler: mainly Merlin 60, 70, and 80 series (1942–1946).

What is not dispute is that the thousands of Lancasters manufactured with Merlin-XXs or the American Packard equivilents had engines that limited their cielings to well under 26,000'! Those engines had single stage blowers. IF the less powerful at altitude and less fuel efficiant Merlin powered Lancasters were required to bomb from 30,000' or higher, both fuel for the return trip and bombs would have to be off loaded before that could happen!I note from your own post that the specially engined Lancs above, had cielings WELL UNDER 29,000'! They were also used in limited ways. I would counter with the fact that the Lancaster with 4X1,635 HP Engines were few and far between1 can you list numbers that actually saw service?

[45-Shooter]

You are right! It's easy and mostly right!

But this argument is being fought with apples Vs oranges. The Lancaster was a good plane. I have never disputed that. It was just not as good as the B-17. ( From some mission profiles and points of view!)
If we specify the bombing altitude to be above 25,000' then the Lancaster numbers start to look a whole lot less impressive. If we specify longer ranges, bomb loads go down. That is a fact of life for every single plane ever made! If we specify day light missions, then the Lancaster's frailty seems down right desperate.
If we consider that the RAF stipulated that more than half of all bombs dropped at night landed OUT SIDE of the target city limits! All of those bombs were thus wasted and the figures must be adjusted; 604,000 tons, more than half of which missed, then 304,000 tons of bombs is the BEST POSSIBLE EFFECTIVE fire power. 304,000 tons divided by 156,000 missions gives just under 3,900 pounds of EFFECTIVE bombs per sortie.
While many bombs dropped by B-17s/24s and other missed their targets, no one on the planet will state that more than a few percent of those misses landed so far away from the target as to miss the entire city! On the other hand, no one has ever shown a picture of a rail yard with over 1,000 bomb craters inside the fence dropped by Lancasters. Under that exact same definition of "Bombs inside the city limits", then the average from B-17s is far higher!

[45-Shooter]

I agree completely!

All our hats should go off to bomber crews! They took more casualties per capita than any other service except NAZI Submariners!
How many men do you know who would get up every morning knowing that many of them would not come back?

[Richard Woods]

45 Shooter;

Shouting the same thing over and over in the face of facts given to you (rather than your own subtle wiki edits) doesn't make it true.

The B17 as a whole is most definitely not 'better'.

1. The statement regarding bomb doors was yours, written in post no. 25. on this thread.

Field modification... a lot more flexibility was afforded B17 crews with various guns being sported in new and crazy configurations. Look through the numerous photo's in the excellent "Lancaster at War" series and you'll see there weren't that many field modifications. Basically, you're making stuff up. I expect to see your edit on wikipedia proving me wrong within an hour or so.

2. I didn't realise we were limited to a particular theatre of operations, I thought we were debating about the aircraft... Look at numbers of Lancasters on any one single mission. The most mustered was 796 on one mission. That is the most aircraft available to use at one single point in history. If we take into account unserviceable and training aircraft it still falls way short of most B17's available at any one time.

3. True, but you don't state how you arrive at less than half the payload for the altitude. You're guessing, and its a bad guess. Especially when known achievements for the Lancaster stand at 22,000lbs to 16,000 feet, several times.

Go look at the NFxxx serial batch of aircraft, used by 617Sqn on the Tirpitz raid. Built by Armstrong Whitworth at Baginton, none are 'Special' aircraft. BI 'Special' aircraft were those fitted for 'Upkeep', or 'Grand Slam' weapons.

The link I posted is correct. If a 'Special' aircraft was needed to carry a weapon, it says so. Look at the section for the 'Grand Slam'.

'Tallboy' could be carried by any normal Lancaster with bulged bomb doors and there were several production batches built that way, including a good number of the Hercules engined aircraft. I'll provide you with production figures later when I have the reference material to hand.

4. Seeing as you seem to be hung up on the Merlin XX which the Lancaster started with, then got rid of after the first BI's - lets look at your chosen in the same way.

How many B17's still had the original variant of the Wright Cyclone that the B17C had way back when it started being part of the war (funnily enough in RAF hands).

Or given that we keep talking modified aircraft how many aircraft got to the end of the war without the redesign of everything aft of the trailing edge of the wing? When a similar thing was done to the Lancaster (extended wing tips, 8 foot fuselage plug aft of the wing) they redesignated it from Lancaster IV to Lincoln.

I'm happy to use limited production aircraft as examples of what the aircraft was capable of. Don't ask me for answers as to what aircraft used things if you don't want an answer you won't like. I realise you don't like this much as it makes the B17 look a little inferior, so I'll limit it to those that saw combat. To help you defend the B17, try digging up some obscure version of B17, like the 'Aphrodite' drones. They had a bit more payload but were disposable...

If you want production numbers by model of Merlin, be prepared to do the same with verified sources for the B17.

5. Seeing as the Lancasters were ordered and built in batches of 300 or so, your point about limiting numbers wouldn't really make a difference. A reasonable number of BII, BIII, and BX aircraft had bulged bomb bay doors too, it wasn't just the BI. However, the limits you want to impose aren't satisfactory... you can't ignore something that actually was built and used in anger, even if in minor numbers. Its all 7,377 Lancasters compared against all 12,731 B17's or not at all.

7. This is what it has to do with things - An indication of how versatile something is is how long it lasts in service, in the job it was designed to do. For instance, the B52 would not be as long lasting at its job if it were of no use.

The fact is, by the time the B17 was throwing retardant on conifers and hauling rancid meat around parts of South America, the Lancaster was still patrolling Canada and a good portion of the Pacific in military service.

Regarding the fires I mentioned, even in preservation the problems continue - one B17 lost during the filming of 'Memphis Belle' and more recently the Liberty Belle burning to a cinder. Further back into wartime, look at why the wingtip vents were fitted to the B17. According to the 4th Bomb Wing, USAF - it was to cut down on unexplained wing explosions believed to be fuel vapour build up.

We all know that the B17 could get up to 35,000 feet or so - but the service ceiling isn't its bombing altitude, its a measure of how high it can fly before the climb rate suffers. I can't find record of a B17 bombing anything from it service ceiling, but research suggests typically the B17 did its job at 20,000 feet.

For higher altitudes we can bring in the B17 replacement - the B29; an altogether more worthy contestant against the Lancaster.

You points about accuracy in your latest post bring up interesting areas for discussion, in that accuracy improved during the course of the war. By the end with the use of Pathfinders, it was a very accurate process resulting in destruction of cities. The process was copied by the USAF and put into practice against Japan.

The 'frailty' in daylight missions is known right from the Lancaster's birth. But when you consider sheer firepower in defensive armaments (and the B17 was designed to be defensive) the Fortress was superior. 13 x .50 guns, against the Lancaster's 8 x .303 spells it out in no uncertain terms.

Regards,

Rich
(self confessed Avro fanatic)

[astir 8]

I had half an hour inside the BBMF Lanc at Fairford in 2010 and took a lot of photos of the interior. Should anyone want copies PM me. Or if someone knows the system for posting them on PPrune also let me know.

The men who flew Lancs were much braver than me. A very long and difficult route to the exits for most of the crew.

p.s. The only armour I could see was the pilot's seat back. Certainly none in the turrets.

Don't know why you guys are arguing about Lanc vs B17. Totally different mission configurations. Both great aircraft.

[Brewster Buffalo]

that the RAF stipulated that more than half of all bombs dropped at night landed OUT SIDE of the target city limits

I think this is a reference to the May 1941 report by Bomber Command but was this true in 1944/1945 with the better navigation aids and the pathfinder force?

They took more casualties per capita

I can quote another RAF study in 1942 which gave these statistics on the percentage chance of survival of one tour by role

Heavy & Medium Bombers 44%
Day Fighter 43%
Torpedo Bomber 17%

[45-Shooter]

Rebuttal/argument

The B17 as a whole is most definitely not 'better'.

2. I didn't realise we were limited to a particular theatre of operations, I thought we were debating about the aircraft... Look at numbers of Lancasters on any one single mission. The most mustered was 796 on one mission. That is the most aircraft available to use at one single point in history. If we take into account unserviceable and training aircraft it still falls way short of most B17's available at any one time.
About numbers, you list all Lancs Vs all B-17s. Yet B-17s were used in four theaters of operations and Lancs in only one. There are many reasons why there were <800 Lancs available at any one time. They were built, used and destroyed at such a rate that less than 800 were available at any given time during the war. From your post. They were less reliable than the B-17 and had a much lower mission readiness rate than the B-17. The typical bombing altitude of American missions varied between 25,000' and 31,000'! Some at almost 35,000'. No mission was ever scheduled to operate at less than 25,000' over the target. This was the minimum altitude considered necessary to avoid the most dangerous Flack. Most Lanc missions were under 17,000' over the target, NONE were at altitudes over 25,000'! Just curious; What was the maximum number of B-17s sent on any single day against the Nazis?

3. True, but you don't state how you arrive at less than half the payload for the altitude. You're guessing, and its a bad guess. Especially when known achievements for the Lancaster stand at 22,000lbs to 16,000 feet, several times.
How does lifting 22,000 pounds to 16,000' relate to the failure to lift any weight to 30,000'? IIRC, the maximum ceiling of the loaded Lanc with 14,000 pounds of bombs up was under 19,000'? So dropping 8,000 pounds of bombs off of the manifest adds 3,000'. The secret is that the fuel for the return flight must be on the plane after it drops the bombs and thus limits the ceiling that can be reached before the bombs are dropped. The Lanc's poorly blown engines is why it has a ceiling more than 10,000' lower than the B-17! This is a function of three things; Wing Loading, L/D and available power at altitude. The B-17 was the more aerodynamic of the two planes. This is not open to debate. They both had about the same MTO of 65,000 pounds and about the same EEW. They had similar wing spans and areas, yet the B-17 was faster and longer ranged than the Lanc with LESS INSTALLED POWER! Thus it had to have a better L/D.

Go look at the NFxxx serial batch of aircraft, used by 617Sqn on the Tirpitz raid. Built by Armstrong Whitworth at Baginton, none are 'Special' aircraft. BI 'Special' aircraft were those fitted for 'Upkeep', or 'Grand Slam' weapons.
Except that they were fitted with the much more powerful version of the Merlin engine! Most Lancs did not use this engine! In my book that made them "Special"! Could that mission have been flown with the much less powerful type XX Merlin engine? Not on your life!

'Tallboy' could be carried by any normal Lancaster with bulged bomb doors and there were several production batches built that way, including a good number of the Hercules engined aircraft. I'll provide you with production figures later when I have the reference material to hand.

4. Seeing as you seem to be hung up on the Merlin XX which the Lancaster started with, then got rid of after the first BI's - lets look at your chosen in the same way.
Still waiting for you to list how many Lancs were built/retro-fitted with the RR made Merlins, Vs how many were made with American made Packard Merlins? Note that WO the exact numbers in front of me, every book I have, stated that MOST Lancs were built with Packard built Merlin engines, not RRs. Every last one of those was the American Version of the Merlin XX.

I'm happy to use limited production aircraft as examples of what the aircraft was capable of. Don't ask me for answers as to what aircraft used things if you don't want an answer you won't like. I realise you don't like this much as it makes the B17 look a little inferior, so I'll limit it to those that saw combat. To help you defend the B17, try digging up some obscure version of B17, like the 'Aphrodite' drones. They had a bit more payload but were disposable...Along those lines, except for the 33 "Specials", the maximum bomb load for the rest of the >7,000 Lancasters was 14,000 pounds! The vast majority >8,000 B-17s could carry 17,600 pounds of bombs. ( Winner= B-17)

If you want production numbers by model of Merlin, be prepared to do the same with verified sources for the B17.

5. Seeing as the Lancasters were ordered and built in batches of 300 or so, your point about limiting numbers wouldn't really make a difference. A reasonable number of BII, BIII, and BX aircraft had bulged bomb bay doors too, it wasn't just the BI. However, the limits you want to impose aren't satisfactory... you can't ignore something that actually was built and used in anger, even if in minor numbers. Its all 7,377 Lancasters compared against all 12,731 B17's or not at all.
FINE! B-17s dropped 640Kt to Lancasters 608Kt! In Europe only, the B-17s also dropped 138Kt on Japan. Does that count toward the B-17s score, or do we use only those bombs dropped on Nazi/Axis targets?

7. This is what it has to do with things - An indication of how versatile something is is how long it lasts in service, in the job it was designed to do. For instance, the B52 would not be as long lasting at its job if it were of no use. But a much more accurate assessment would be when the owners could afford to replace obviously obsolete equipment with jets!


We all know that the B17 could get up to 35,000 feet or so - but the service ceiling isn't its bombing altitude, its a measure of how high it can fly before the climb rate suffers. I can't find record of a B17 bombing anything from it service ceiling, but research suggests typically the B17 did its job at 20,000 feet. Wrong assessment! The minimum bombing altitude over Europe was 25,000'!

For higher altitudes we can bring in the B17 replacement - the B29; an altogether more worthy contestant against the Lancaster.True, but not relevant to this argument!

The 'frailty' in daylight missions is known right from the Lancaster's birth. But when you consider sheer firepower in defensive armaments (and the B17 was designed to be defensive) the Fortress was superior. 13 x .50 guns, against the Lancaster's 8 x .303 spells it out in no uncertain terms.
So very true!
Regards,
Rich
(self confessed Avro fanatic)
Regards,

Stewart
( Self confessed Strategic Bomber fanatic!)

[Richard Woods]

Stewart,

Unless you start accepting what you read in books and other published papers, we're going nowhere.

About numbers, you list all Lancs Vs all B-17s. Yet B-17s were used in four theaters of operations and Lancs in only one. There are many reasons why there were <800 Lancs available at any one time. They were built, used and destroyed at such a rate that less than 800 were available at any given time during the war.

Not really an argument about the aircraft there as the superior manufacturing capacity of the USA is known. You're missing my point. When comparing tonnage, you've been talking total bombs dropped by the B17 as a type. The only way to get a true comparison would be to put equal numbers of each aircraft side by side and compare them.

From your post. They were less reliable than the B-17 and had a much lower mission readiness rate than the B-17.

Prove it? In terms of single aircraft, they often flew on far longer - look at numbers of aircraft that got over 50 missions. Or over 100.

Compared against the B-17 and B-24s - where after a couple of their crew did 25 missions they got classed as war weary, painted in funny colours and used as 'Assembly ships' - its no contest.

The typical bombing altitude of American missions varied between 25,000' and 31,000'! Some at almost 35,000'. No mission was ever scheduled to operate at less than 25,000' over the target. This was the minimum altitude considered necessary to avoid the most dangerous Flack. Most Lanc missions were under 17,000' over the target, NONE were at altitudes over 25,000'! Just curious; What was the maximum number of B-17s sent on any single day against the Nazis?

Unfortunately they didn't avoid the flak or the fighters. Reading 91st BG, 303rd BG and various other 8th AF records show bombing heights of around 23,000 ft. None below 25,000 eh? Read on.

The most B17's I can find on one mission was 453 B17's to Cologne in October 1944. Having said that, I don't have specific numbers as I do for the Lancaster.

How does lifting 22,000 pounds to 16,000' relate to the failure to lift any weight to 30,000'? IIRC, the maximum ceiling of the loaded Lanc with 14,000 pounds of bombs up was under 19,000'? So dropping 8,000 pounds of bombs off of the manifest adds 3,000'. The secret is that the fuel for the return flight must be on the plane after it drops the bombs and thus limits the ceiling that can be reached before the bombs are dropped. The Lanc's poorly blown engines is why it has a ceiling more than 10,000' lower than the B-17!

I've pointed out to you twice now - bombing height and ceiling aren't the same. I've found a couple of reference to B17's in the Pacific bombing from 30,000 ft, but no details of the load.

To answer your question though; lifting 22,000lbs to 16,000 ft is related to the B17's attempts to get 17,600lbs to the same height, for substantially less range.

This is a function of three things; Wing Loading, L/D and available power at altitude. The B-17 was the more aerodynamic of the two planes. This is not open to debate. They both had about the same MTO of 65,000 pounds and about the same EEW. They had similar wing spans and areas, yet the B-17 was faster and longer ranged than the Lanc with LESS INSTALLED POWER! Thus it had to have a better L/D.

You've only got to look at the Lanc to realise its not the most aerodynamic aircraft in the world. Its wing isn't designed for speed either, its there to lift a heavy weight at low speed... something it did quite well into the 1990's.

Except that they were fitted with the much more powerful version of the Merlin engine! Most Lancs did not use this engine! In my book that made them "Special"! Could that mission have been flown with the much less powerful type XX Merlin engine? Not on your life!

Apart from the very first batch of Lancasters there were few that had Merlin XX engines... about 900 aircraft out of 7,377. I posted this further back in the thread, this highlights your ignorance. The NFxxx batch were STANDARD BIII AIRCRAFT. "Special" aircraft were designated as such.

Still waiting for you to list how many Lancs were built/retro-fitted with the RR made Merlins, Vs how many were made with American made Packard Merlins? Note that WO the exact numbers in front of me, every book I have, stated that MOST Lancs were built with Packard built Merlin engines, not RRs. Every last one of those was the American Version of the Merlin XX.

Indeed, and you'll notice that Packard never built the Merlin XX, they produced the Merlin 28 which was based on it, and re-engineered. In regards of numbers around 3,030 Packard equipped Lancaster BIII were built, out of 7,377.

Along those lines, except for the 33 "Specials", the maximum bomb load for the rest of the >7,000 Lancasters was 14,000 pounds! The vast majority >8,000 B-17s could carry 17,600 pounds of bombs. ( Winner= B-17)

I posted the Lancasters loads, yet you've ignored them. I also posted the woeful performance of the B17 when given 17,600lbs to carry.

Admittedly the Lancaster regularly carried 14,000lbs. What did the B17 carry on a regular basis?

8,000lbs.

Winner = Lanc.

FINE! B-17s dropped 640Kt to Lancasters 608Kt! In Europe only, the B-17s also dropped 138Kt on Japan. Does that count toward the B-17s score, or do we use only those bombs dropped on Nazi/Axis targets?

Just keep it to a representative number. For example - If I had one aircraft and you had two, and we both sent them out against the same targets at the same time; you'd drop more. If we take one aircraft of mine, and one of yours, it becomes more representative between aircraft rather than operator.

But a much more accurate assessment would be when the owners could afford to replace obviously obsolete equipment with jets!

Find me an available jet that could do the job the Lancaster was doing in Canada in the 1960's, or in the Pacific.

Wrong assessment! The minimum bombing altitude over Europe was 25,000'!

No, I think you need to go read some more. Here's a part of an article by John T Correll, for Airforce magazine.

"Postwar analysis found that accuracy had been about the same in Europe and Asia for day visual and radar precision bombing. Eighth Air Force in Great Britain put 31.8 percent of its bombs within 1,000 feet of the aim point from an average altitude of 21,000 feet. Fifteenth Air Force in Italy averaged 30.78 percent of its bombs within 1,000 feet from 20,500 feet. In the Asia and the Pacific, Twentieth Air Force—45.5 percent of whose sorties were daylight precision despite the emphasis on area bombing in the last months of the war—put 31 percent of its bombs within 1,000 feet of the aim point, although the bombing altitudes were on average 4,500 feet lower than for Eighth Air Force"

Note he says 'average' not 'minimum'.


Summing up?

B17 =

Faster at higher altitude. Comes at the cost of range and payload. Daylight missions required nearly 4,000lbs of payload capacity used by defensive armament, which though substantial is barely adequate.

Lancaster =

Ultimate heavy lifter, only rivalled by the B29. Versatile in terms of bombload, due to uninterrupted 33 feet long bomb bay. Runs out of breath at higher altitude. Poor defenses.

Crews of both aircraft =

Heroes.


Regards,

Rich

[Agaricus bisporus]

From a popular song of the time, to the tune of The Battle Hymn of the Republic, aka John Brown's Body

We're flying Flying Fortresses at thirty thousand feet
We're flying over Germany to give the Huns a treat
We've bags and bags of ammo and a teeny-weeny bomb
And we drop the bastard from so high we don't know where it's gone

Fer Chrissakes, the Mosquito had a better bomb load (and a bigger bomb bay??) than a B17. Whats there to have a discussion about re the Lanc? As a bomb truck the B17 wasn't even in the same class. It might have been better for inter-crew football matches I suppose...

[Weheka]

Interesting, what targets and dates did the B17 drop (138kt?) of bombs on Japan, and where did they launch these missions from? I haven't read much on the bombing campaign against the Japanese mainland, thought it was pretty much all B29s plus a few B24s and of coarse B25s.

Both the Lancaster and B17 were great aircraft (not normally referred to as "planes") of WW2, but I would side with Richard, who seems know exactly what he is talking about, on which one packed the most punch.

Also, any one who is a self confessed "fanatic on strategic bombers" surely would not confuse Flak with "Flack"?

[longer ron]

The Lancaster regularly carried 14,000lbs. What did the B17 carry on a regular basis?

= 8,000lbs.

Richard I think you are being too kind to the B17 there - for the long range missions deep into germany the bomb load would have been 4,000 lbs.

In the funny 'logic' of the military procurement cycle...one could argue that the B17 was a complete failure at its primary role,on early raids into germany they got mauled by fighters and flak and could only achieve acceptable losses with heavy fighter escort.
So one could argue that the B17's best defensive weapon was (say) the P51 - and once the P51 became operational (late 1943) then (to use Bullshooter45's favourite expression) perhaps the B17's could have been field modified to remove some of its defensive armament to improve a/c performance!
Please note that I am not grinding an ax(e) about the B17,it was the fault of the military 'planners' - who thought that the bombers could get through unescorted.

Another little facet of the B17 war (perhaps B24 also ?) was that only a small proportion of the a/c (formation/deputy + possibly element leader) used the bombsight...the rest of the bombardiers 'toggled' when they saw the leader drop.

As I said - I dont have any axes to grind here,I have been an aircraft engineer for 40 years so I do not look at any aircraft through rose tinted specs...they are all a compromise engineeringwise.
If I had been a Heavy Bomber pilot in WW2 then there is no doubt I would have chosen these 2 a/c types to fly!
The B17 because she was easy to fly and was a tough bird !!
The Lanc because she was a pilots a/c -the controls were definitely the most ergonomic of the brit heavies.

[Mac the Knife]

"PS, did you know about the losses from Schlang muzak because the bottom ball turret was removed for night bombing?"

It was "Schräge Musik" [Jazz] not "Schlang muzak" (sic.)

Schräge Musik - Wikipedia, the free encyclopedia

Mac

[stilton]

Surely points made with vast amounts of red ink must be a true reflection of history

[rolling20]

I suggest one looks at the BOMBER COMMAND LOSSES 1939-45 by William R. Chorley.
Lancaster losses from 1942 onwards are shown with a 7 man crew, sometimes 8 if 101 Squadron operated or if an aircraft carried a 'second dicky' along.
If no mid upper turret was being used, then what on earth was the mid upper doing on board? End of argument.

[45-Shooter]

You confuse strategic demands with aerodynamic potential?

Stewart,There are many reasons why there were <800 Lancs available at any one time. They were built, used and destroyed at such a rate that less than 800 were available at any given time during the war.

You're missing my point. When comparing tonnage, you've been talking total bombs dropped by the B17 as a type. The only way to get a true comparison would be to put equal numbers of each aircraft side by side and compare them.

From your post. They were less reliable than the B-17 and had a much lower mission readiness rate than the B-17.

Prove it? In terms of single aircraft, they often flew on far longer - look at numbers of aircraft that got over 50 missions. Or over 100.
I've tried to do this several different ways and each time you change the subject or twist the point, but here goes again from the top;
The B-17 carried on average, less bomb tonnage per mission as reflected in the total tonnage divided by the number of missions flown! IIRC, about 4,000 pounds for the B-17 force Vs 7,800 pounds for the lancaster force total.
The Lancaster force required almost 8000 planes and one or two years longer to do this. There were never that many B-17s in England!
Of the ~7,000 B-17s sent to England, almost a thousand less than the total production of Lancs, they flew for about a year less. SO, less B-17 planes flew MORE missions than Lancaster planes in fewer years and dropped more tonnes of bombs. They were able to do that because the Engines were much more reliable than the Merlins in the Lanc.
The bomb loads and distances were determined by strategy and tactics, not the various planes ability to carry bombs over range! That has absolutely nothing to do with it.
The typical bombing altitude of American missions varied between 25,000' and 31,000'! Some at almost 35,000'. No mission was ever scheduled to operate at less than 25,000' over the target. This was the minimum altitude considered necessary to avoid the most dangerous Flack. Most Lanc missions were under 17,000' over the target, NONE were at altitudes over 25,000'! Just curious; What was the maximum number of B-17s sent on any single day against the Nazis?

Unfortunately they didn't avoid the flak or the fighters. Reading 91st BG, 303rd BG and various other 8th AF records show bombing heights of around 23,000 ft. None below 25,000 eh? Read on.
There is a differance between schedualed and actual, but that does not change the fact that the 8th AAF flew more missions in less time or that their consistant average altitude was higher!

The most B17's I can find on one mission was 453 B17's to Cologne in October 1944.
You missed the schwinfurt raid with ~660 bombers, IIRC.

I've pointed out to you twice now - bombing height and ceiling aren't the same. I've found a couple of reference to B17's in the Pacific bombing from 30,000 ft, but no details of the load.

To answer your question though; lifting 22,000lbs to 16,000 ft is related to the B17's attempts to get 17,600lbs to the same height, for substantially less range.
Any planes ability to carry load is inversely proportional to the range, ceiling and speed at which it does it.
Flying higher requires more throttle. That shortens range. That lowers bomb load that can be carried. Because air rarifies at a constant manner as one ascends, the difference in weight can be used to calculate the exact ceiling that a plane can reach with any given load, IF you know the ceiling with some other load. Do those calcs!

You've only got to look at the Lanc to realise its not the most aerodynamic aircraft in the world. Its wing isn't designed for speed either, its there to lift a heavy weight at low speed... something it did quite well into the 1990's.

Except that they were fitted with the much more powerful version of the Merlin engine! Most Lancs did not use this engine! In my book that made them "Special"! Could that mission have been flown with the much less powerful type XX Merlin engine? Not on your life!

Apart from the very first batch of Lancasters there were few that had Merlin XX engines... about 900 aircraft out of 7,377. I posted this further back in the thread, this highlights your ignorance. The NFxxx batch were STANDARD BIII AIRCRAFT. "Special" aircraft were designated as such.

I can see that we are useing the same word for different meanings. According to Janes, page 106, PP 5; The Lancaster B Mk-III was the same plane as the B Mk-I except it was fitted with Packard built Merlin 28s, which were exactly the same as RR built Merlin XXs! 1280 HP! As far as I can see, all other Merlin engined Lancs were "Modified" as in "Special"! out of the ~8000 built, less than 100 had any Merlin engine that made over 1400 HP and they were probably all out of the B Mk-I batch.

Still waiting for you to list how many Lancs were built/retro-fitted with the RR made Merlins, Vs how many were made with American made Packard Merlins? Note that WO the exact numbers in front of me, every book I have, stated that MOST Lancs were built with Packard built Merlin engines, not RRs. Every last one of those was the American Version of the Merlin XX.

Indeed, and you'll notice that Packard never built the Merlin XX, they produced the Merlin 28 which was based on it, and re-engineered. In regards of numbers around 3,030 Packard equipped Lancaster BIII were built, out of 7,377.
Exactly my point! The vast majority of Lancs, >7,000, had SINGLE STAGE ENGINES! Also according to Janes, on the same page; The Maximum bomb load at 1,000 miles range was 14,000 pounds! Just to clarify that point; If you used 100% of the fuel to fly the mission, WO leaving any reserve, it could fly 500 miles, drop the bombs and return, but only if you did not use any fuel forming up or waiting to land. That means that in practical terms, you could send them 400-450 miles at the most, if they did not form up into groups.

Along those lines, except for the 33 "Specials", the maximum bomb load for the rest of the >7,000 Lancasters was 14,000 pounds! The vast majority >8,000 B-17s could carry 17,600 pounds of bombs. ( Winner= B-17)

I posted the Lancasters loads, yet you've ignored them. I also posted the woeful performance of the B17 when given 17,600lbs to carry.

I forgot the load list you posted because it was not relevant at that point. Since that time, I have found that less than 40% could carry the heavier, 18,000 pound load. B Mk-IIIs only! Of course discounting all 387 with engines of more than 1,280 HP, including 300 B Mk-IIs. (I have yet to find the maximum standard bomb load of the B Mk-II!)
Again from Janes; on page 210, B-17 Range with maximum bomb load at 220 MPH = 1,100 miles, or about 100 miles farther than the Lancaster with 3,600 pounds less bombs. So much for the differance in L/D!
Admittedly the Lancaster regularly carried 14,000lbs. What did the B17 carry on a regular basis?8,000lbs. Winner = Lanc. Much less! about 4,500 pounds on average! The average of all Lancaster missions was about 7,800 pounds. Effects of lower operating altitude and shorter operational range AS DICTATED BY THEIR RESPECTIVE MASTERS!! HAVING ABSOLUTELY NOTHING TO DO WITH AIRCRAFT PERFORMANCE!

Just keep it to a representative number. For example - If I had one aircraft and you had two, and we both sent them out against the same targets at the same time; you'd drop more. If we take one aircraft of mine, and one of yours, it becomes more representative between aircraft rather than operator.

So on to the analysis;
1. The EEW of the B-17 is slightly less than the Lancaster's Empty Equipped Weight!
2. Both aircraft have the same MTO, or Maximum Take Off weight about 65,000 pounds.
3. The BEST B-17 has less available power than any Lancaster variant! ( 1,200 to 1,280!)
4. Depending on model, altitude, weight, etc, the B-17 is between 13 and 30 MPH faster than the Lancaster! ( Any Lancaster!)
5. Therefore, it has a better L/D and is more efficient aerodynamically.
6. I could go on about fuel tankage and SFC, but that would be superfluous.
If the Lancaster was made with Packard engines, IE, a B Mk-III it could carry 18,000 pounds to a range of <800 miles. That is a heavier bomb load than any B-17 could do, but the drawbacks were, less range, mixed larger and smaller bombs, lower altitude, depending on model, 16,000 to 19,500' and with less speed. On the B-17s side it could drop four identical 4,000 pounders, carried internally, with actual weights about 3,850 pounds to a range od 1,250 miles and an altitude of 26,500'.
Find me an available jet that could do the job the Lancaster was doing in Canada in the 1960's, or in the Pacific. This is relevant how?

Wrong assessment! The minimum bombing altitude over Europe was 25,000'!

No, I think you need to go read some more. Here's a part of an article by John T Correll, for Airforce magazine.

"Postwar analysis found that accuracy had been about the same in Europe and Asia for day visual and radar precision bombing. Eighth Air Force in Great Britain put 31.8 percent of its bombs within 1,000 feet of the aim point from an average altitude of 21,000 feet. Fifteenth Air Force in Italy averaged 30.78 percent of its bombs within 1,000 feet from 20,500 feet. In the Asia and the Pacific, Twentieth Air Force—45.5 percent of whose sorties were daylight precision despite the emphasis on area bombing in the last months of the war—put 31 percent of its bombs within 1,000 feet of the aim point, although the bombing altitudes were on average 4,500 feet lower than for Eighth Air Force"

Note he says 'average' not 'minimum'
I have not seen this article! Taking it at face value American bombing altitudes were lower than most other authors have written. But how does that lower altitude stack up Vs the well under 20,000' or barely over 15,000' for most Lancaster missions?

Summing up?
B17 =

Faster at higher altitude. Comes at the cost of range and payload. Daylight missions required nearly 4,000lbs of payload capacity used by defensive armament, which though substantial is barely adequate.

1. The EEW of the B-17(any), INCLUDING the 4,000 pounds of armor, ammunition and weapons was about 1,000 pounds less than the EEW of the Lancaster. Different more advanced construction techniques. Really bad point since the B-17 was started ~half a dozen years before the Lanc? I think, my personal oppinion that is, is that the differance in weight was caused by the added metal required to strengthen the 33' long bomb bay which protruded long beyond the wing spar(S) which supported it? ( Can't remember if it had one or two?)
2 . This is the entire point! With any given weight of bombs the B-17 will fly farther at higher altitude and faster! You keep failing to differentiate between what the plane could do and what the masters wanted it to do! This is not a small difference. It is between 11-20% advantage to the B-17 depending on model and mission parameters!
Lancaster =

Ultimate heavy lifter, only rivalled by the B29. Wrong! Versatile in terms of bombload, due to uninterrupted 33 feet long, but very low bomb bay. Runs out of breath at higher altitude. Poor defenses, and fragile construction WO much armor.

If I had to summarize this last, I'd say that the long bomb bay was more versatile in that the B-17 witch could only carry bombs up to 10' in length. But the B-17's bomb bay was divided in half and twice and a half as tall. It was possible, but very rarely done, to carry two 4,000 pound standard medium case American bombs on each of the two sides, one above the other, FOUR total! It is imposable for the lancaster to match this load. While I do not know the CoG limits, I do know that hanging two 1,000 pounders on the last two racks was, if not forbidden, restricted, because if they failed to release, the plane was lost due to aft CoG excursion. The standard Lanc could not carry this bomb at all because it was too fat to fit inside the regular bomb bay doors! That is why they built the "Cookie"! While it might be possible to fit three of these monsters on the CL hooks, in a plane with bulged doors, I sincerely doubt that anyone would do it for the
afore mentioned CoG reason if the last bomb hangs up.
If you limit your argument to later model Lancasters with the requisit capacity to carry 18,000 pounds, it can carry 400 pounds more bombs than the B-17, but to a much shorter range! If we ask that the maximum weight of incendiary bombs be carried, then the B-17 with it's 42 bomb shackles, to the Lancs 15, wins hands down! What type of bomb did the RAF switch to late in the war when the discovered that fire bombs were five and a half times as effective at high explosives? It can load up to 40 each 440 pound incendiary cluster bomb units! Not that this would normally be done, but loading 34 in each B-17 was done on at least one occasion that we have pictures of! 34X440 pounds = 14,960 pounds! How many pounds of incendiaries could the lancaster carry from the charts you posted previously?

But now the Piece de la resistance! How would the two aircraft have done if their respective missions were swapped?
The Lancaster forced to fly over Nazi held Europe in broad day light WO fighter cover and in the face of visually directed Flack? We already know how the B-17 faired. But let us take an excursion down fantasy lane;
1. The Lanc has to add 4,000 pounds of armor, weapons and ammunition. Subtracting the same weight from pay load! ( Just to make absolutely certain that we all understand this point, remember that the Lancaster's average bomb load for the war was under 8,000 pounds and the B-17's over 4,400, which means that the B-17 has a >700 pound edge!
2. The rest of the planes fragile construction makes it much easier to shoot down than the B-17. Bad luck!
3. The lower speed and altitude makes it much easier to intercept. More chances for the fragility to suffer 20-30 MM Cannon hits. More bad luck!
4. The slower cruising speed means that the bomber is over enemy territory longer, again providing more chances to the Luftwaffe to intercept! OOOH that's gotta hurt?
5. The lower altitude makes it easier for Nazi Flack to get hits. ( The standard formula for this is the square of the difference in range.) If 20,500' in the B-17, verses 19,000 feet in the Lancaster makes 16.4% more losses to Flack. But wait, the Lanc is more fragile and near misses would be more likely to down the plane. Very more bad luck! But wait, if the Lanc bombs from a more typical altitude and the Fortress from a higher altitude, say 25,000' Vs 16,000' then the Nazi Flack is 244% more likely to hit! This is not as big a thing as it sounds given that losses to Flack were 1~2% at worst including medium level bombing by B-25s and 26s. But when you consider that there were 787 planes on the raid you mention, that is an extra 21.4 planes lost?
6. The reduced L/D requires the Lancaster to carry fewer bombs and more fuel to distant targets. That means more missions to any single target, thus more chances to intercept. More shuttle missions landing in Russia. There are just too many permutations of this line of argument to continue with a straight face.

On the other side of the coin;
The B-17 gets to shed 3,000 pounds and carry more bombs to a longer range than the Lanc by a huge margin. The weight of fuel for the return to base trip is less by the L/D of that weight. Or they just keep the armor and dump some of the crew and waist guns/ammo? Or wait, they dump it all but the tail gunner and ventral ball turret gunner, pilot, co-pilot, and bombardier/radio operator. Five crew is a thousand pounds plus the weight of the armor protecting them, may be 2000 pounds to play with. OR shed all of the turrets and six crew, it is according to one poster here 50 MPH faster! What if after switching mission profiles the B-17 was modified just for night missions? Then it would be almost as fast as a Mossy, fly higher, may be, and certainly carry much more bombs! How hard would it be to down a B-17 with Mossy speed and B-17 toughness? Right!

Now you tell me which is the better plane! Crews of both aircraft =

Heroes. Absolutely!!!


Regards,

Stewart.

[45-Shooter]

Good one!

Good one! I am the first to admit that my CFS rotted brain is not the best around. I do not have a clue what I was thinking?

[45-Shooter]

Quote:
The Lancaster regularly carried 14,000lbs. What did the B17 carry on a regular basis?

= 8,000lbs. Richard I think you are being too kind to the B17 there - for the long range missions deep into germany the bomb load would have been 4,000 lbs.
No! For really long ranges it would have been closer to 2,000 pounds!

In the funny 'logic' of the military procurement cycle...one could argue that the B17 was a complete failure at its primary role,on early raids into germany they got mauled by fighters and flak and could only achieve acceptable losses with heavy fighter escort.
This is absolutely true! The first B-17s were pathetic, armed with 5 X .30 caliber RCMGs. The second batch had 6 X .30s! It was not until the B-17E that the plane was equipped with an additional 3,600 pounds of armor, weapons and ammo, including ten to eleven .50 caliber HMGs. Note also that the B-17 at least according to the Germans, SHOT DOWN MORE Nazi planes than any other type! More than any other type! ( It bears repeating!)
So one could argue that the B17's best defensive weapon was (say) the P51 - and once the P51 became operational (late 1943) then (to use Bullshooter45's favourite expression) perhaps the B17's could have been field modified to remove some of its defensive armament to improve a/c performance!
I like that idea! Suppose that the Lancaster and B-17 had been forced to switch rolls? The Lanc bombs during the day and the Fortress at night! Strip out most of that armor, weapons and ammo. Relocate the flight deck to the bomb aimer's level, plate over the flight deck bulge and windshield, all the turrets and extraneous gun positions, leaving only the tail gunner with a crew of four! Now it is as fast or faster and higher flying than the Mossy B Mk-VI and caries much more than twice the bomb load to much farther ranges! WOW!
Please note that I am not grinding an ax(e) about the B17,it was the fault of the military 'planners' - who thought that the bombers could get through unescorted.
Again, you are absolutely right about that! It was also the Military leaders that chose the mission profiles that made the one plane look better than it was and the other to appear to be less than it was!

Another little facet of the B17 war (perhaps B24 also ?) was that only a small proportion of the a/c (formation/deputy + possibly element leader) used the bombsight...the rest of the bombardiers 'toggled' when they saw the leader drop.
Again, This is absolutely true!

As I said - I dont have any axes to grind here,I have been an aircraft engineer for 40 years so I do not look at any aircraft through rose tinted specs...they are all a compromise engineeringwise.
Again, This is absolutely true! But you tell me honestly that given one plane is faster and higher flying on less power at the same weight, span and WA, it then has to have a better L/D and supirior drag plot, does it not?
Edited to fix typos.

[45-Shooter]

In the Philipins and other targets in the Solomons and Marianas. I meant to say PTO and substituted "Japan" instead. Also should have had a decimal point between the three and eight.

[45-Shooter]

Quote; "Fer Chrissakes, the Mosquito had a better bomb load (and a bigger bomb bay??) than a B17. Whats there to have a discussion about re the Lanc? As a bomb truck the B17 wasn't even in the same class. It might have been better for inter-crew football matches I suppose..."

Really? A Mossy can tote 17,600 pounds of bombs? Roughly half of the Lancs built could not carry more than 14,000 pounds!
Range of the Lanc with 14,000 up was 1,000 miles. Page 106 of Janes. The B-17 could haul the maximum load of 17,600 pounds to 1,100 miles! Page 206 of Janes. Remember that is round trip range with the bombs left half way and no reserve in either case! That makes the true "Radius of Action" with reserves about 400-450 miles! Lets see... more pounds of bombs to longer range for the B-17???
Right!