Ptak Science Books

Ultra-Massive Acceleration, Jules Verne, and Making Human Jelly. A Romance of 22,000 gs

JF Ptak Science Books   Post 1722     

[My apologies to my readers:  in an earlier version of this post I calculated that the Verne space module would be traveling 129,000,000 mph exiting the space cannon--that was wrong, I'm very sorry to say. The figure should have been 129,000,000 feet per hour, which would be about 25,000 mph.  Mea culpa.]

Earlier in this blog appeared a post on the Eiffel Tower Happy Bullet.  It turned out to be a highly-circulated bit, what with the subject matter and all--describing a gigantic bullet filled with people and dropped from the interior heights of the Eiffel Tower and landing in a big watery hole at the bottom.  The effect of impact I think would have made those folks suffer Massive Internal Complications.

Impressive as the Eiffel bullet idea was, it was absolutely nothing compared to what another Frenchman thought of at about the same exact time.  Perhaps no human could have suffered more internal disruption in any science fiction story than those who would have been subjected to Jules Verne's (whose birthday is today, February 8, 1828 – March 24, 1905) space gun, an enormous Columbiad, the mode of propulsion for the travelers in his From the Earth the Moon/De la Terre a la Lune.

Verne's 20,000-lb projectile to the Moon would sit in a cannon-hole in the Earth that was 280 meters deep with a diameter of 2.7 meters, which would sit on the bottom of the hole capping off  200 feet of guncotton (!, weighing 400,000 pounds!).  Somehow this mass would be ignited, and as Verne (or his brother) calculated would produce an initial velocity of 12,000 yards per second, which is 36,000 ft sec, or about 24,000 mph, which is a big enough number to attain the (more or less correct) escape velocity V_e  of 11.2 km/sec. (Very high-velocity shells  fired by tanks fitted for kinetic energy penetrator ammo attain a muzzle velocity of 5700 ft/sec.) And somewhere in there would be a crew greeting a rather-ncredible-to-write-down 22,000 gs.  Astronauts in the Apollo program experienced something like 1g; dragster car drives who go from 0 to 100 mph in .86 seconds experience about 5.4g.  

22,000gs is another thing entirely.

And difficult to imagine.

Jules Verne got a lot of stuff right in his long and lovely career--an there was quite a bit that he foretold correctly in this very story.  Just not the take-off. 

The further-funny thing about this space gun is that it made another appearance in another Verne story, The Purchase of the North Pole, 1889.  During this period of human exploration there was a push to explore the Poles--in Verne's story, an attempt is made to simply this exploration.  But not in the way you might think.  Verne was going to employ the space gun, again, but this time to alter the axis of the Earth so as to make it easier to get to the Poles and exploit their natural resources.   I must say that this answer was not at all clear to me, even with my best sci fi cap on:  but Verne saw it, saw that it would be better for all concerned to move the Poles rather than moves towards them. And that's some pretty big thinking.

Anatomy of the B-17: Construction Images from Seattle, 1941/2.

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I've long been an admirer of the Boeing B-17 aircraft and have posted about it on this blog a number of times.  Today I just wanted to share some images of the aircraft's production and assembly at the Boeing Seattle works in 1942.  All photographs are from the Farm Security Administration series (Office of War Information) and can be found (with a hundred others) at the Library of Congress site, here.

(Our younger daughter, Tess, with here antique wooden model of the B-17, with the real thing (B-17G)  in the background.)

Farm Security Administration/Office of War Information Black-and-White Negatives:  B-17 Construction, 1942-1944

"Production. B-17F heavy bombers. A women worker, over 60 years old, does an expert riveting job on a B-17F bomber in the Long Beach, California, plant of Douglas Aircraft Company. Better known as the "Flying Fortress," the B-17F is a later model of the B-17, which distinguished itself in action in the South Pacific, over Germany and elsewhere. It is a long range, high altitude, heavy bomber with a crew of seven to nine men and with armament sufficient to defend itself on daylight missions."

What was Dropped from the Skies First, the Mails or Bombs?

JF Ptak Science Books   Post 1717

Seeing this splendid image of the 1909 near-future forced a question into mind:  what came first, aerial delivery of mail or aerial delivery of explosives?  I suspected that "mail" would be the correct answer, but didn't know how much deeper that went into the past than the history of aerial bombing.

 

The first bits of mail were delivered among the first balloon flights ever made--in the U.S., the first quasi-official piece of airmail was a letter from president George Washington that went aloft in the first balloon flight (1793) in this country, deliverable to whomever it was that first came to greet the balloon in wherever it landed.  The first semi-regular delivery of mail in the U.S. was again by balloon, beginning in 1859, which still precedes the first sustained use of explosives dropped from aerial vehicles by five decades.

 

This image was drawn by H. Janos for the Illustrated London News for 16 January 1909, and shows a futuristic balloon making its way from Dover to Calais with a cargo of mail and a dozen or two passengers (and whatever crew there was besides the captain, presumably belowdeck).  The article reads: "1910 may seem a very early date at which to fix the coming of such vessels, yet aerial navigation is progressing at such a rate that none can call the date impossible". 

And so true;  it didn't take but a few years to begin experimental air service routes for the mails by biplane, and less than a dozen to have instituted long-range flights by heavy aircraft, with the mammoth mail-delivering airships sent to the not-good ideas department. 

In any event I just happen to like this image by Janos--for what was a not-essential piece to the weekly magazine, the man did produce an admirable work, not the least of which is his unusual airborne oblique bird's-eye view to the shoreline. 

Living Aloft, 1920

JF Ptak Science Books  Quick Post

D.G. Lloyds certainly had an interesting--if not unique--vision of non-stop or uninterrupted cross-country aerial service, writing about Non-Stop Landing of the Future (Illustrated World, May 1920.)  And for Lloyds the future was soon, or tomorrow, because, frankly, the technology was there, if not the will.  Or the inclination.  Or the presence of a logic for creating such a service.

It seems to me that after floating along for days at 75 mph (or thereabouts?) that, after finally getting across the country, a traveler might want to simply disembark.  But this behemoth envisioned by Lloyds wouldn't have to actually stop--it was outfitted, designed to release/accept passengers while in flight.  Now of course take-offs and landings are the most dangerous parts of flying, and perhaps this is what Lloyds was trying to replace.  But to me it looks like he replaced one significant danger with, well, several other significant dangers. 

Look:  it just seems to me that any time you have a giant airplane synchronizing flying with an enormous dirigible to transfer exceptionally heavy cargo at an altitude of one mile that there is some substantial room for pilot(s) error.(s) and other freak whatevers.  Also, the issue of using dozens of men with shepherd hooks to grab a multi-ton object suspended from a moving platform to another moving platform seems to me, well problematic.  But it does make for a pretty picture.

Amelia Earhart's Disappearing Hand and Her Not-Disappeared Greatness

JF Ptak Science Books 

(I just added a few things to this post from three years ago.  The image of Ms. Earhart's hand is fantastic--read the story here in the post Amelia Earhart: Her Physical Disappearance vs. Lindbergh's Moral Vanishing):

Monsters in the Clouds--Conan Doyle and High Flight

JF Ptak Science Books    Post 1688   (Part of the series on the History of Blank, Empty and Missing Things--Upper Atmosphere Monsters.)

Illustrated World for July-August 1920 asks the question "Will Man Soar to Unknown Heights" and indeed, they answered in the affirmative, saying that the "heights of space instead if the depths of the seas or the distant poles are to beckon the adventurous,  according to scientists who are making a specialty of the atmosphere".  In what must seem to the modern reader to be an enormous and naive statement of the obvious, the future aviators would fly in "glass enclosed fuselages" in order to gain great heights.

There would however be no monsters--except for lack of oxygen and the cold.  he editors did mention a Conan Doyle story in which monsters lived at high altitudes, monsters that were form-changers, much like the clouds they lived above.  This was his "The Horror of the Heights"(1913), a short story about a flyer named Joyce-Armstrong who longed for great heights--and for the "something else" that was up there, something dark and sinister that lived in the stuff that we breathe, as the story is told through the pages of a recovered, blood-stained notebook found in a field. We learn that Joyce-Armstrong was a dreaming pragmatist, longing for the ethereal of great heights but loathe of it also, aware of a danger so great that he carried a shotgun along with him in flight.  We read in the flight book that the aviator had an experience at 40,000 feet, meeting a new air-jungle world of semi-formed gelatinous creatures, one of which has a more solid form with tentacles and a beak, and does battle with them, surviving, returning to the ground.  He vows to go back, at which point we assume he met his doom. 

In 1913, an altitude of 40,000 feet was extreme, the record at the time being about 9,000', and that reached in a Wright biplane--quite an achievement I think for such an aircraft,  By the time this article appeared in 1920, the record altitude was 33,000', which at least got a lot closer than the 9k' of 1913. The aircraft for this record--the LUSAC-11 (Lepère United States Army Combat) was much more considerable than the Wright plane, though it seems to me a work of fantastic skill/effort/courage to take such a thing so high.

Aeroplanes & Airships: Artistic Displays of Quantitative Data, 1914

JF Ptak Science Books 

In another adventure in infographics and the artistic display of quantitative data we find this pair of very distinctive images that seems to work, a little:

[Image source:  5 September 1914, vol 112, #10,  Scientific American.]

The graphics are mostly good if not a little clunky--they can be viewed as "scary".  Mostly, though, these images are reproduced today because I find it hard to pass up an interesting airship illustration, though they do present their case more clearly than a slightly earlier attempt at data display seen last week on this blog.

The images for the distribution of naval power are very defined:

(I especially enjoyed the comparison of naval guns, with the cannon-within-a-cannon.)

Rockets to Outer Space, 1923

JF Ptak Science Books    Post 1657

This is some beautiful thinking and work by the rocket pioneer, Hermann Oberth (1894-1989)--the teacher of Wernher von Braun, a highly functioning leader at the Nazi V-1 and V-2 base of Peenemunde, and of course after the war working for various aeronautical/astronautical concerns in Switzerland, Italy, Germany and the United States. In America he would work for von Braun at Huntsville, Alabama from 1955-1959 on the Army's ballistic missile program,  a late addition to the many German scientists scooped up right after the war in Project Paperclip and deposited in the Deep South. 

The gorgeous design above is the front wrapper of his rejected doctoral dissertation, Die Rakete zu den Planetenbraeumen ("The Rocket Through Planetary Space" or "The Rocket to Interplanetary Space"), published in Oldenbourg in 1923.  Oberth's work was printed in a very small edition and even at that he had to pay for part of the pamphlet's printing--it turned out that the work was an instant success when issued, selling out quickly.  A second edition vastly expanded the original's 92 pages into 429 in 1929. 

 

In Old Testament vocabulary, Oberth's work is Genesis for space travel and aeronautics--or at least he is one of two or three authors of Genesis, along with Goddard and Hohmann.

 

As it turns out, in his extra moments, Oberth served as a technical advisor to Fritz Lang on his film, Frau im Mond, and his influence shows, even from cursory examination.

Big Numbers and WWII Aircraft--Artistic Displays of Quantitative Data

JF Ptak Science Bools  Quick Post

This post continues an earlier series on the artistic display of quantitative data--putting a face on big numbers. In particular it extends a collection of images of Second World War airplanes, "A Big Sea of Planes:  Quantitative Display of World War II  Bombers. The images below appear in the 17 October 1942 issue of the Illustrated London News in an article about the possibility of replacing seaborne troop and materiel transport across the Atlantic from America with the big Martin JRM Mars aircraft, getting the troops there faster and safer and releasing at least part of the naval force for wartime activities.  The images are pretty compelling:

 The caption states that 5000 Mars planes could get 500,000 soldiers to Europe.

 These were big planes¹ (200' wingspan, 117' long, 38' high, more below) and could haul 130+ troops.  By the time though that the powers-that-be were figuring out who the main contractor would be for production (and those production numbers in early 1942 were about 500 per year, at that point, anyway) the Battle of the Atlantic was already--in 1943--fairly well decided.  The U-Boot problem was solved enough for a continuous flow of soldiers and supplies, though not without a high cost in the first half of the Atlantic campaign.  (Overall, from 1939 to 1945, some 3,500 Allied merchant ships  and 175 Allied warships were sunk, costing the lives of 72,200 Allied sailors and merchant seamen.  The Germans lost more than 780 submarines along with fully three-quarters of all sailors in the U-Boot fleet, making some 30,000 men.)

 Below, a cutaway for the Mars:

Stats and Technical data on the Glenn-Martin(from Jane’s Fighting Aircraft of World War II, (1945):

Rooftop & Floating Airports -and!- Rooftop Airports in a Levitating NYC, 1929

JF Ptak Science Books   Post 1652  (Part II of an earlier post on Rooftop Airports, here.)  Part of this blog's History of the Future series.

I really just wanted to post these two images before I lost them again. I've written earlier here about high-rise, in-town/downtown airports settled on the tops of buildings (or loaded onto newly-constructed structures over rivers and etc.), but these two images offer a nice distinction on the height's of elevated airports of the coming future.  The first is by the great Paul Frank, and appears in Amazing Stories for 1928:

The taller of the two airports seems to be 75 stories above the ground, maybe more--its hard to tell.  It is interesting to see that there is another (of no small size) right next door, but not quite so high.  The 500'-tall elevated walkways/roads are impressive.

In April, 1936 another artist saw an even taller airport, which caps off an enormous building that seems at least not only twice the height of the Empire State Building (just newly completed), but also far wider.  If you made the "...tropolis" airport signifier on top the midway of the landing field, I calculate the width of the building to be at least 600', meaning it would be something like 250x600', or about four acres (or more) per floor.  Big building, with an enormous volume. 

[Picture source:Modern Mechanics, April 1935, as pictured in Dark Roasted Blend]

 

[Picture source: Paleofuture.com]

And here, another big rooftop creation of a 16x17 checkered grid, complete with, well, nothing at all, not even guard rails or fences--this would be rooftop-airport-landing Old School.  The runways aren't even particularly long, though I have no doubt that the magazine's cover space dictated most of the size, anyway. 

Of course the idea of very-elevated high-rise airports become secondary when you introduce the idea of floating/flying airports, as we see in this fantastic idea by (again) Frank Paul in the July 1929 issue of Air Wonder Stories. (This image and next from frankwu.com website dedicated to the artwork of Frank Paul, a great and wonderful thing.)

And of course when the idea of the flying airport fails, you can always go for the flying city, with airport:

 

This is again Frank Paul, from November 1929's Amazing Air Stories, and depicts--of course--New York City removed from the ground to levitate, above its former self. Luckily there isn't just a hole in the ground where is used to be, the rock and bedrock picked up along with the buildings and the rest of the (non bridge) infrastructure.  It is still a busy place. I presume that given the crowding of the place that there are still high-elevation rooftop airports in the floating city. 

There are other sorts of air-borne airports, though they are mainly built on/in large airplanes and airships, and really don't qualify for a post on the simple rooftop airport.  Perhaps it is time now for an all-inclusive Odd Places for Airports post to appear here...

For example:

 The magnificent possible, 1924, saw another kind of airborne airport:

 

History of Lines: Looking Straight Down from Straight Up, 1786

JF Ptak Science Books   Post 1581

I was struck by the mosaic possibilities of the image (below) found in Thomas Baldwin's Airopaidia (printed in 1786) and so made it into one.  But what the engraving is,m really, is a view from a balloon, looking straight down.

We're looking straight down, through the clouds, seeing two towns (at bottom-left and top-center)--why the rivers are red, I don't know.

There are other posts on this blog on looking straight down, which is an attractive subject--to me, at least. First-hand images of looking straight down fro a balloon are rare things, even through the early 19th century, and offer a prospective seldom seen in human history.

Another view from this work attempts to show some depth:

Here's another view of that same image from the Baldwin experience, reprinted around 1810, and left in black-and-white:"

 Halton Tuner makes these observations on Baldwin's flight in his iconic Astra Castra: Experiments and adventures in the atmosphere ¹(published in 1864 in London): 

When the "Standard" Wasn't So--Flying Upside Down, 1913

JF Ptak Science Books   Post 1565

Nearly everything that we have or use or see today was at one point "new"; standard practices, commonly used implements or technologies or ideas were at some point a breakthrough, wholly uncommon, completely non-standard. This thought struck me while breezing through an issue of The Illustrated London News for September, 1913, and seeing the following headline:

The Wright Brothers made their powered flight in 1903, and  it is a testament to the difficulty of performing  upside-down flying that it took nearly 10 years to accomplish.  And so it happened, Adolphe Pegoud (1889-1915) accomplishing the feat 21 September 1913--he was greeted everywhere as a pioneer and a hero.  Flying upisde down, looping he loop (the distinction of "first to do this belongs to the Russian Nesterov who performed it in Kiev about a month earlier), doing the tail-slide, performing the vertical S, were all major feats, and all performed by Pegoud during this month of high activity.  But the people who seemed to take the quickest and most particular interest in these "stunts"  were the military folks, who instantly recognized the application of the maneuvers for aerial combat.  And as quickly as they saw that the maneuvers needed to learned for offensive purposes, they recognized that they must be mastered for defensive reasons, as well.  

New York Times reported on Pegoud so:  (via The Daily Planet at the Smithsonian Air and Space):

"Pégoud prepared a Blériot monoplane fitted with a Gnome engine and advised half a dozen friends of his plan. They did their utmost to dissuade him, but he invited them to witness the performance, and this morning at the Juvisy aerodrome he climbed into the machine and rose. At the moment of his departure he was by far the calmest person present.

He rose to a height of 3,000 feet and then turned the nose of the machine earthward. For 200 feet it fell like a stone. It then turned inward till it was flying on its back, after which it rose perpendicularly upward. Then it completed the circle by regaining its normal flying position, having accomplished an apparent impossibility.

The aviator came again to earth absolutely self-possessed. When he alighted from the machine his first remark was “I wished I had gone another thousand feet up. Then I could have done it twice.”

The issue of Sciewntific American for (October, 1913)

Image Source: Pionnaire GE

Long ago Sir Thomas Browne mused on what it was that the Sirens' song might have been, trying to imagine and capture a source of vast imagination; it is equally complicated trying to understand how something we take so deeply for granted today was absorb when it was seen for the first time. 

What Was the Strategic Cost of the V-1 and V-2 to the Nazis?

JF Ptak Science Books   Post 1551

One of the defensive weapons in the Allies' arsenal during WWII may have been the V-1 and V-2.  This sounds horrible to say, and I don't mean this application intentionally, of course--but the production of the V-1 and V-2 was something that could have caused the Nazis the equivalent production of something like thousands (dozens of thousands?) of fighter aircraft--a part of the Luftwaffe that he Allies didn't need to shoot down because they were never built.  As horrible as it sounds, the V-1 and V-2 may have been the far greater thing to choose from in the production of multiple evils.

The Vengeance Weapon was a great-ish achievement of the Nazi regime, intended to strike enough fear and destruction in London and other cities and to render them a shambles, an effort that was thought would bring the Brits to their knees.  What happened, though, was this:  that in all of the raids and bombings at the hands of the V-weapons, much of the attack was lost to going off-course, unable to find their gigantic target.  Over time, the V-1 and V-2  terror weapons did kill 9,000 people  or so in the U.K. in their  raids from 1944 and 1945, wounding 25,000  and destroying 20,000+ houses. Over 11,000 of the V-weapons were fired by the Nazis:  more than 9,100 V-1s were fired at Britain (with 2,500+ hitting London), while 1,115 V-2s were launched.   They were terrible weapons, and they killed many people--overwhelmingly a civilian population--but they performed nowhere near their strategic intentions. 

These totals for the entire campaigns of the V-1 and V-2 rockets  are less than those of a single large raid by Bomber Command, sometimes less than one mission, on one night.  The massive expense involved in producing the V-1 and V-2 weapons could well have been used to fabricate 5 or 10 or perhaps 25 thousand fighter planes.  Fighter planes that could have been used in the war on offensive and defensive procedures. That's 25,000 fighter aircraft that never flew for the Luftwaffe, never terrorized anyone, never flew in defense of German cities, never had to be shot down. (Assuming of course that the Germans would have had the fuel to power them.)

They were terrible weapons--the V-1, in particular, made a very dirty, nasty sound, that was a terrifying experience to hear.  When the sound of the engine stopped, the bomb fell.  Long, throaty, deathly gurgle,then silence, then explosion.  The V-2s came in mostly silently, a masked death, but in so doing also somewhat mollified a significant psychological terror weapon.

Perhaps I am way off base with this, but the V-weapons seem to me to have cost the Nazis far more than they gained.  Of course if they had been able to produce an order of magnitude--or more--of the weapon and delivered it more effectively, then perhaps it becomes a different story.  It would have been a different story too if the Germans had had any reliable intelligence on the effectiveness of the weapos so that they could have adjusted their flight, and if Ultra had not existed, and so on down that ridiculous rabbit hole of speculation.  But my own idea remains that the V-weapons were not as horrific as other things could have been had those resources been allocated differently. 

Aerial Bombing Accuracy Calculator, WWII

JF Ptak Science Books  Post 1545

I found this object in my paper-calculators box (moveable disk calculators made of paper, two going back to A. Kircher in the 1660’s)—I’m not sure why it was there as it is not paper, though it is an interesting calculator.

[Images are greatly expanded in click mode.]

I learned a big lesson from it.   The “Small Target Bombing Probabilities” calculator was issued by the insufferably-little-known Applied Mathematics Panel of the National Defense Research Council (NDRC)¹ in the early 1940’s during WWII. 

Marked “Restricted”, it calculated the number of bombs that would successfully be delivered given (1) the number of bombs, (2) the “aiming error”, and (3) target size. It would then generate results for “(a) the expected number of hits for the indicated number of bombs”, (b-e) the probability of at least one hit to four hits.

What is surprising to me was the number of bombs that didn’t find their target. For example, a 70,000 square foot building bombed with 200 bombs had a 50% chance of landing within 1200’ of the target’s center, and one in 100—or 2 bombs of the 200—will find their mark.  I don’t think that I’ve ever seen figures like this before, and I’m surprised at the 1% hit rate.

Notes

1. The establishment of the NDRC was announced so: “It is announced by Science Service that the following committee has been appointed in the United States to correlate "scientific research on the mechanisms and devices of warfare": -- Nature 146, 191-191 (10 August 1940).

“Members included: Dr. Vannevar Bush (chairman), president of the Carnegie Institution of Washington, formerly dean of the faculty of engineering at the Massachusetts Institute of Technology; Prof. Richard C. Tolman (vice-chairman), dean of the graduate school and professor of physical chemistry and mathematical physics at the California Institute of Technology; . Dr. Irvin Stewart (secretary), formerly Federal Commissioner for Communications and chairman of the Committee on Scientific Aids to Learning; Rear Admiral Harold G. Bowen, director of the Naval Research Laboratory, Anacostia, D.C.; Conwiy P. Coe, U.S. Commissioner of Patents; Dr. Karl T. Compton, president of the Massachusetts Institute of Technology, formerly professor of physics at Princeton University; Dr. James B. Conant, president, formerly professor of organic chemistry, Harvard University; Dr. Frank B. Jewett, president of the Bell Telephone Laboratories; Brigadier General G. V. Strong, assistant chief of staff, U.S.”

The "Other" Hiroshima: Hamburg, Operation Gomorrah, Summer 1943

JF Ptak Science Books   Post  1543

It was during the spring and summer of 1943 that the Allies came to the conclusion that the idea of strategic bombing needed to be expanded--the expansion part grown to include the total destruction of the target city. 

The "most secret" letter¹ (dated 27 May 1943)  that outlined the coming approach to aerial bombing was sent by Air Chief Marshal Arthur "Bomber" Harris  to his six group commanders and detailed the more-new strategic approach to bombing cities--the city itself would be a strategic target, with the goal in this case of destroying the entire city.

Operation Gomorrah occupied four nights from 24-30 July, involving 791 aircraft on the 24/25th, 90-110 B-17s on the 25th, 131 B-17s on the 26th, 787 aircraft on the 27/28th,  777 on the evening of the 29/30th., and finally with 740 aircraft on the night of the last raid on 2/3 August.3,000+ aircraft were employed in the action dropping 9,000 tons of bombs.   At the end of the Gomorrah campaign, 42,600 people had been killed as well as almost 40,000 wounded, destroying about half the homes int the city and causing another million people to flee the city.  The greatest amount of damage and death occurred on the night of the 27th, when 787 British aircraft caused an enormous firestorm to be formed, at one point fueled by a 1500'-foot tall tornado of fire, which caused 150 mph fire winds, temperatures reaching so high (1800 degrees and more) that it  set the asphalt streets on fire.  Most of the dead were killed by asphyxiation, the oxygen pulled out of bomb shelters and hiding places to be used in the fires.  The infrastructure of the city had been largely destroyed before this day's bombing, so getting firefighting crews to any of the new scenes would be impossible.  As a matter of fact, there was so much smoke generated from the previous day's bombings that the USAAF B-17 attacks were suspended because targets could not be identified. 

 

And from this point to the end of the war there were another 60+ campaigns flown at Hamburg, attacking and re-attacking oil storage facilities, shipbuilding industries, U-Boat factories, and the like.  53 missions involving several thousand aircraft, flying against the re-supplking and ruined city right to the end of the war, including 5 major actions in the last week of the war. 

I don't think that this was its own "Hiroshima" as British command thought, because, well, Hiroshima and Nagasaki have their own categories for destruction.  As does Tokyo. And Dresden.  It does though share a newness of bombing with Hiroshima in establishing the mission against Hamburg as a mission against an entire city rather than specific targets--certainly there were specific targets in mind for the hour or more worth of aircraft, but the overall effect was to support a carpet bombing plan and to initiate a fire so massive and destructive that the entire city would succumb.

Newsreel of the bombing of Hamburg.

Notes

1.   The Harris ltter:

MOST SECRET

---

BOMBER COMMAND
OPERATION ORDER NO. 173
Copy No: 23 Date: 27th May, 1943

---

INFORMATION

The importance of H A M B U R G. the second largest city in Germany with a population of one and a half millions, is well known and needs no further emphasis. The total destruction of this city would achieve immeasurable results in reducing the industrial capacity of the enemy's war machine. This, together with the effect on German morale, which would be felt throughout the country, would play a very important part in shortening and in winning the war.

2. The 'Battle of Hamburg' cannot be won in a single night. It is estimated that at least 10,000 tons of bombs will have to be dropped to complete the process of elimination. To achieve the maximum effect of air bombardment, this city should be subjected to sustained attack.

Forces to be Employed

3. Bomber Command forces will consist of all available heavies in operational squadrons until sufficient hours of darkness enable the medium bombers to take part. It is hoped that the night attacks will be preceded and/or followed by heavy daylight attacks by the United States VIIlth Bomber Command.

INTENTION

4. To destroy HAMBURG.

[Source]