Was the Mosquito the worlds first stealth aircraft?

[pbfoot]

Originally Posted by Soren

I fully agree.

The versions of Go-229 built weren't so by slave labor though, and AFAIK only Bf-109 production to a small extend utilized slave labor within the aeroplane industry. Ammunition and some small arms production plants utilized the most slave labor late in the war.

and Focke wulf and BMW and Heinkel .
"The named plaintiffs in the suit include Russian born Tatianna Zaitseva and Ukrainian borne Olena Ovechkina, both of who are now permanent United States residents. Zaitseva and her mother, a physician, were transported by the Nazis to Focke-Wulf Flugzeugbau, a subsidiary of Daimler-Benz, where they were forced to work as slave-labors for nearly four years"

Eastern European Survivors of German Slave Labor File Class Action Against Industry Giants; Suit Targets Daimler Chrysler, BMW, Bayer Others for Wartime Use of Slave Labor | Business Wire | Find Articles at BNET.com

[Soren]

Originally Posted by FLYBOYJ

A small radar signature - yes. A blob? I doubt it,

Wrong about the jet engines too - even if surrounded by radar absorbing material - in this case wood, the intake and exhaust would show up. The area has to be "diffused" as done on the F-117 and B-2. That technology wasn't even thought of by anyone in WW2.

The Mossie and Go-229 could be considered "stealthy" but no way by intention.

Bottom line, Dave hit the nail on the head....

I disagree as he makes it sound like jet engines give higher radar signatures than propeller engines.

I never claimed that the jet engines wouldn't deflect the radar waves and give away a signature, only that it wouldn't show as big a signature as a propeller engine. Also the very shape of the Go-229 would make sure that the Allied radar equipment of the time wouldn't be able to distinguish it from a large bird. The jet engines are the only good wave deflectors on the Go-229.

[Soren]

Originally Posted by pbfoot

and Focke wulf and BMW and Heinkel .
"The named plaintiffs in the suit include Russian born Tatianna Zaitseva and Ukrainian borne Olena Ovechkina, both of who are now permanent United States residents. Zaitseva and her mother, a physician, were transported by the Nazis to Focke-Wulf Flugzeugbau, a subsidiary of Daimler-Benz, where they were forced to work as slave-labors for nearly four years"

Eastern European Survivors of German Slave Labor File Class Action Against Industry Giants; Suit Targets Daimler Chrysler, BMW, Bayer Others for Wartime Use of Slave Labor | Business Wire | Find Articles at BNET.com

Great little google search, only problem is that's a law suit Pbfoot.

I know BMW used slave labor to some extent, but still it wasn't in a very significant fashion and not within the aero industry. Focke Wulf didn't use any slave labor for a/c production, however it did use a few for the production of some simple parts which didn't demand any expertize to manufacture.

[FLYBOYJ]

Originally Posted by Soren

I disagree as he makes it sound like jet engines give higher radar signatures than propeller engines.

Believe it or not, depending the way they are configured within the structure, a jet engine could give a HIGHER signature than a recip. The only way to accurately determine is to place an aircraft on a radar test range. This is what one would look like

Originally Posted by Soren

I never claimed that the jet engines wouldn't deflect the radar waves and give away a signature, only that it wouldn't show as big a signature as a propeller engine.

Originally Posted by Soren

Also the very shape of the Go-229 would make sure that the Allied radar equipment of the time wouldn't be able to distinguish it from a large bird.

Again, there would be no way to determine that...

Originally Posted by Soren

The jet engines are the only good wave deflectors on the Go-229.

See first response.

[Soren]

The way the Go-229's engines are configured into the airframe means a lower signature than that given away from a piston engined fighter. The frontal area of the Go-229's engines is also allot smaller than that presented by a propeller.

And as to the shape, well flying wings have smaller radar signatures than regular a/c.

[FLYBOYJ]

Originally Posted by Soren

The way the Go-229's engines are configured into the airframe means a lower signature than that given away from a piston engined fighter. The frontal area of the Go-229's engines is also allot smaller than that presented by a propeller.

To a point - unless the intakes are diffused the compressor or turbine (if painted from the rear) is going to show up, and the signature will be very large.

Originally Posted by Soren

And as to the shape, well flying wings have smaller radar signatures than regular a/c.

Agree....

[davparlr]

Unless you test the shape, or do a statistical analysis, you can only guess about the RCS with a low probability of being anywhere accurate. Without this data, declaring a design as stealty is not valid. Unless one knows the tested RCS of the Go-229, one really knows nothing. Also, unless you know the performance of 1945-46 Allied radar in range vs. RCS, you also don't anything about its performance against that threat.

Soren, Where did you come up with the comment that jet engines have a less RCS than a piston plane? It certainly can't be area or size, since that really has little to do with RCS (RCS reflectors used in test and decoys can be very small but emit a very nice signature, the very small Quail duplicated the huge B-52). RCS is an extremely complex concept and is certainly difficult to generalize.

[JoeB]

A missing piece here (seems to be, unless it's way back in the thread, sorry to repeat if so) the power relationship between target radar cross section (RCS) and detection range for a given radar. The detection range varies as the fourth power of the RCS. IOW halving the RCS cuts detection range by only 15%; you need a 99% reduction in RCS to cut detection range by 68%, 99.99% to cut it 90%. You just can't get that kind of reduction by accident of simple choice of material (and in only part of the plane!) or of general shape. As was said, just a screw head sticking out a little somewhere could ruin a really meaningful reduction in detection range, and the computational and testing tools for true VLO design didn't exist. Even when the F-117 was designed those tools were cruder than when B-2 and F-22 were.

A similar thing comes up sometimes comparing modern basically non-LO planes with *some* low observables design mods and treatment (for example F-18E/F's, EurofighterTyphoon, B-1B v B-1A etc) with real VLO planes. The signature is very signficantly reduced in the treated/partially redesigned planes compared to other conventional planes, but not enough to radically reduce detection range. It's a modest reduction in *detection range*, for modest cost. There's no easy way to real stealth now either.

As for WWII and modern radars, the basic physical principals haven't changed. One reason many radars in WWII had low resolution is they operated on low frequencies, eg. the gigantic British 'Chain Home' early warning arrays that operated in HF>bottom of VHF band. Such radars are actually less susceptible to VLO measures in principal, because they only 'see' *any* plane as a vague disturbance across a few wavelengths. The specific shape or reflectivity of the materials in the wing or fuselage makes less difference at those frequencies; those measures mainly affect higher frequency radars. Efforts to detect the presence of modern VLO planes, if not track them accurately enough to engage, are often based on reverting to lower frequencies (but no free lunch: big, immobile, vulnerable, low resolution radars).

WWII fire control radars OTOH were directing weapons, AA guns, with very short ranges by today's stds. Within the few mile practical range of a Flak 88 even a modern VLO a/c might be detected by a Wurzburg fire control radar (again the 4th power law). Wooden contruction alone wouldn't make a plane invisible to such a radar within the small effective envelope of the weapon it was directing.

The modern VLO's advantage is in the modern situation, where radars and weapons systems require *precise* targeting at relatively *long range* (as of a SAM or radar AAM) in order to cope with a plane effectively: effective VLO design and tactics will respectively deny that long range capability, and avoid coming close enough to lose the advantage, but if they do come close enough they will lose it. The WWII situation was different and the range reduction just from accidental choice of material or basic shape would be much less. It's questionable IMO whether wooden construction or general flying wing arrangement would make an appreciable difference in effectiveness of radars, in the WWII situation. I think some TV and written accounts that suggest otherwise are overlooking some basic facts.

Joe

[FLYBOYJ]

Great info guys - and again I repeat...

The Mossie and Go-229 could be considered "stealthy" but no way by intention.

[Seawitch]

Much is being made of the GO-229, or Horton.
I've only just discovered it existed thanks to this thread, but did recognise it as something seen in a signature on here.
I've been away to read about that.(wikapedia)s Only one prototype was built and flew just two hours. That won't be news to people talking about it I'm sure.
But it certainly wasn't built with stealth in mind, but range....to meet a '1000, 1000, 1000' range, payload and speed requirement by Goring.
I can't say it's the equivalent to a Mosquito I wondered might exist....does anybody have an idea about that?

[delcyros]

...according to Dr. Reimar Hortens account on his Ho-IX / Go-229, it was intentionally layouted with design, plywood surfaces and some kind of special paint to have a lower radar signature. One of the purposes was as an attack bomber, another was as a nightfighter where even marginal improvements come in handy.

However, Horten wrote his account in the 60´s, I believe. It is the main source for claiming the Ho-IX was kind of an stealth plane.

[Soren]

Yes, the Go-229 was meant to be covered with RAM. The prototypes weren't however because of the budget cuts.

[Seawitch]

Germany was dabbling with a rubber coated submarine to overcome Sonar, I'll see if I can find more out.
I thought that would be difficult...
Anti sonar coat for U boats

[delcyros]

The usual snorkel coat was not anti sonar but anti - radar.
The rubber coating is employed on the snorkel, the only part of the boat to be surfaced when recharging the Diesels. It doesn´t make sense as an anti-sonar suite for surfaced parts while the rest of the submerged body (=HUGE reflection area) is not covered by this suite. It does, however, come in handy against anti submarine patrol airplanes and their airborne decimetric radarset...
Only full hull treatments had any effect on sonars but it is not known how many boats received this.

[davparlr]

Originally Posted by FLYBOYJ

Great info guys - and again I repeat...

The Mossie and Go-229 could be considered "stealthy" but no way by intention.

I still have to disagree. Without really knowing the tested or analized RCS, we cannot say whether they are stealty. Materials, shapes, RAM, all have to be applied properly to be effective. For the Stealth of today, lots of dollars, big brains, and very large computer programs were required to reduce RCS by orders of magnitude in order impact even crude radars, as was very capably explained by JoeB. You would be surprised by the relatively small reduction in detection range of the B1B compared to the orders of magitude larger RCS of the B-52.