The Best Bomber of WWII: #4

[FLYBOYJ]

If the thrust provided drives the machine, then what would you call the directed thrust flow, if not a "jet"

A garden hose supplies a "jet" of water , & a carburetor a "jet" of fuel, & a leaf blower a "jet" of air.

A jet comes out of the reduced orifice - what happens up stream of that is the determining factor. for that reason was the Space Shuttle a jet?

 

[FLYBOYJ]

Oh no not wiki!
Seriously though, from wiki: "A rocket engine is a type of jet engine".

And seriously, the Me 163 IS NOT a jet. Now please get this thread back on subject.

 

[FLYBOYJ]

Of course, the SS used various kinds of "jets" including "jets" to make subtle docking manoeuvres in orbit.

Called "thrusters" that carried their own oxidizer and couldn't be fully controlled. Now back on subject

 

[wuzak]

Full Definition of jet engine

1. : an engine that produces motion as a result of the rearward discharge of a jet of fluid;specifically : an airplane engine that uses atmospheric oxygen to burn fuel and produces a rearward discharge of heated air and exhaust gases — see airplane illustration

Definition of JET ENGINE

The way I see it is that technically a rocket can be a jet but that convention has defined a jet engine to be a gas turbine since rockets have proven to be impractical for aircraft.

Jet engine is often used to describe gas turbines that are not actually jets - as in gas turbines for industry/power generation, in boats, trains, cars or propeller powered aircraft.

Then there are jet boats which can be powered by piston motors or gas turbines, but which are propelled by a jet of water from a nozzle.
Jetboat - Wikipedia, the free encyclopedia

 

[FLYBOYJ]

Yeah that wiki definition is convention for elementary school kids, don't try it in a academic/technical/scientific thesis

Or on a flight line in front of a bunch of maintenance engineers!

 

[Shortround6]

No indeed, using the B-29 was convenient, once LeMay ok'd it, even if it was overkill as a mission task.

Hardly "overkill".

The first mining mission involved 105 aircraft. There were 13 attacks by Japanese Aircraft up to another 60 were spotted but did not attack (one might think of multiple claims here and try to figure if there were multiple sightings of the same aircraft.)
Defensive gunners claimed one Tony. Gunners opened fire when the attacking Japanese fighters did according to the report. Mild evasive maneuvers were used. 1. the AA fire varied in intensity depending on target area, On this night with 105 aircraft two mine fields were laid. The total distance of the flight was 2878 nautical miles. 2. The AA Barrage over the straight shot down 3 B-29s, heavily damaged 3 more and caused light damage on 5 more, mild evasive maneuvers were used. 3.
Of the 105 aircraft planned for the mission 3 failed to take-off an 5 returned without dropping mines in primary or secondary locations.
2nd mission 3 nights later involved 85 aircraft.

Now lets imagine using C-54s for the first mission.
point 1. the C-54s have NO defensive fire. Japanese fighter attacks were weak but against planes offering NO defensive fire would they have been bolder or pressed their attacks harder?
Point 2. 2878 nautical miles is 3311 stature miles. Payload of a C-54 (in 1945) over 3300 miles is nowhere near 12,000lbs meaning more planes needed or repeat visits to the same target area needed to get the mine density desired.
Point 3. B-29s had passive protection. There was at least some armor at crew positions and at least some of the fuel tanks were self sealing, perhaps all were, I don't know. The C-54 has NO passive protection. No armor, no self sealing fuel tanks. Losses from damage that allowed a B-29 to return to base could very well have resulted in a loss of the C-54.

Another point. What was the capability of the C-54 to perform even mild evasive maneuvers? I will freely admit that "mild evasive action" is a subjective term and certainly subject to interpretation. However what is "mild evasive action" varies from a fighter to a bomber and from a bomber to a transport. The bomber and transport can really vary in weight at different points in a long flight and allowable maneuvers or "G" loading's can vary along with them. What a Lancaster crew might consider "mild evasive action" considering some of the cork screw maneuvers they used against Luftwaffe fighters might be considered a violent maneuver to a transport pilot.
For the C-54 to even try this mission it needs internal weapons storage (and that means bomb doors) it needs bombing radar and operator. A load that cuts into fuel or payload as does the structural modifications.

Sorry, a C-54 in noway, shape or form can substitute for a B-29 doing long range mining missions.
Now if you want to wait a few more months until the the Navy and Marines can capture Islands closer to Japan and shorten up the flight distance it might have some merit. You are still going to have higher losses than using the B-29s.

 

[wuzak]

Yeah that wiki definition is convention for elementary school kids, don't try it in a academic/technical/scientific thesis

I didn't take it from Wiki, but from Merriam-Webster
Definition of JET ENGINE

 

[Shortround6]

Curiously, a check of the Brit archives at Kew brings up a reference to wind-tunnel testing
being done on the Hawker High-speed bomber design in 1943.

1943 was also the year when the RAF tried using powerful R-2800 engined Lockheed Ventura
bombers in the high-speed precision daylight attack role, but it went badly, VC winning badly.

And tunnel testing in 1943 might lead to flying hardware in 1945. It MIGHT even lead to service use in 1946 if you are really lucky.

As for the Ventura, from wiki "The RAF ordered 188 Venturas in February 1940. They were delivered from mid-1942 onwards. Venturas were initially used for daylight raids on occupied Europe" and lets remember that the Lockheed 18 airliner (airframe the the Ventura was based on) first flew September 21, 1939.

It took a long tome to go from paper or mock up to squadron service. Planning for operations or production needs often meant planing 2-3 years into the future.

 

[Shortround6]

Or, if they'd had a VLR Mustang escort, they could've been bait & wasted the Nippon fighters too.

Yeah, they just needed a VVVLR Mustang escort. Very, Very, Very long range Mustang.
Mustang has Zero chance of returning to base after jettisoning drop tanks at 1600 plus miles from base.

 

[Shortround6]

It was never going to happen.. in 1943 Typhoons were still sitting around waiting for Sabres.

While Merlins were turned out in huge numbers, often going to obsolescent airframes
of little military value, in the 2,000hp & over range, far fewer than 20,000 of the big British engines were built,
as against ~125,000 R-2800s & even enough R-3350s to get the B-29 program up & flying.

I'm sorry, what does engine availability in 1943 have to do with engine availability in 1945/46?

The Sabre was trouble prone in 1943 and was always expensive to build. It may have been an outstanding example of technical sophistication but as a practical powerplant it left an awful lot to be desired for too much of it's life.

 

[Shortround6]

However did they do then? Mustangs were roaming over Japanese skies, from bases in newly captured Iwo Jima.

Mustangs first flew from Iwo Jima about a week after the first mining mission. How long did it take to build up a large number of Mustangs to handle all the duites that were wanted. Mustangs had enough trouble flying the missions they did, daylight escort, without trying for night escort.

 

[wuzak]

Sabre troubles were not a design issue, but an industrial/political production problem, imagine Stalin's solution being applied.

I imagine Stalin would have cut off Sabre production before it began as it was taking too long. He may have dealt with the Napier board as well....

As for cost, what cost the hundreds of Merlins being spread over Germany every month, sometimes even hundreds a night..

And how many more weren't "spread all over Germany"?

Most of the Merlins that went down in Germany late in the war were in Lancasters.

They took with them a big load of bombs. And the vast majority of the Merlins on a mission returned safely with the plane.

 

[Shortround6]

Sabre troubles were not a design issue, but an industrial/political production problem, imagine Stalin's solution being applied.
As for cost, what cost the hundreds of Merlins being spread over Germany every month, sometimes even hundreds a night..

Boy, for person who has trouble bombing cities you seem to have no problem shooting factory workers and managers on your own side.
The "super" mosquitoes powered by Sabres lost a lot of their reason for being when DH fitted two stage Merlins to the Mosquito. Even higher boost ratings on the single stage engines cut into the need. And how many Super Mosquitoes would be needed to replace the 4 engine heavy bombers? Or do you plane to fly 2 missions per night most nights instead of a few times a year? The planned bomb load for these fast twins was 4-5000lbs.

 

[GrauGeist]

What caused it to move then? Would it be the "jet" of gasses expelled through the nozzle at the tail?

I find it interesting that you want to engage in detailed conversations about various warbairds and even go to great lengths to correct me, and you don't even know the fundamentals of a Hydrogen Peroxide rocket motor.

When the two fuel elements (T-Stoff & C-Stoff) were mixed in the Me163's combustion chamber, a violent chemical reaction occurred, causing a violent expansion of volitile gasses...it was this reaction, that was contained and vented out the exhaust nozzle with great force, that propelled the Me163.

And as I mentioned earlier, the propeller on the nose was to provide power to the radio and instruments by way of a generator, since there was no engine in the Me163 to do so.

 

[GrauGeist]

Actually, the Shuttle's and most other satellite's "Thrusters" use mono propellant WO "Oxidizer". Just to be technically correct.

Actually, the RCS systems use NitrogenTetroxide and Monomethyl Hydrazine

To be technically correct

 

[Ascent]

Everyone here should be aware that "jet" in this context is a contraction of turbojet, a gas turbine that relies on the reaction principal to provide propulsion rather than using a free turbine to drive a gearbox that could be connected to a separate propulsion method as in the turboshaft or turboprop. Turbofans weren't in use at this time but also use the reaction principal.

 

[Ascent]

James, much as politicians may wish otherwise simply repeating the same thing over and over again doesn't make it true.

This site is full of people who know what they're talking about and can spot bollocks talkers.

 

[wuzak]

Everyone here should be aware that "jet" in this context is a contraction of turbojet, a gas turbine that relies on the reaction principal to provide propulsion rather than using a free turbine to drive a gearbox that could be connected to a separate propulsion method as in the turboshaft or turboprop. Turbofans weren't in use at this time but also use the reaction principal.

Actually the term turbojet is the combination of turbo for turbine and jet as in "a rapid stream of liquid or gas forced out of a small opening".

 

[Ascent]

After nearly twenty years as a propulsion tech in the RAF I'm quite aware of where turbojet comes from thank you.

The important word in my post was context. Any argument or discussion has a context, wether implicit or explicit. On this forum the context is implicit and is framed by the nature of the board itself. To bring in an argument from outside of that context indicates that either you are unaware of the context or are deliberately ignoring it.

In philosophical circles I'm sure that would make you look smart, unfortunately on a technical forum such as this where those who generally comment are aware of the context and are of a technical nature by inclination it just makes you look like an arse.

Not aimed at you Wuzak.

 

[pbehn]

A jet is a jet because it didnt have a propellor and sends the hot gas through an orifice, the rocket pre dates all of them and is a rocket.