Deckplan Illustrations: What is the issue??

[captainjack23]

Another consideration is that the hull of an advanced ship can be highly radar absorbent - IIRC, one of the technologies researched for the B-1 was a layered lattice structure that attenuated or trapped the radar emission. Plus, by tech 10+, radar absorbing properties are routinely added to the paint of a scoutship. So....radar checks in, but it doesn;t check out. No bounce, no signal, no detection.

On another track, one of the tricks grossly non-stealthed aircraft like the B-52 use is to fly at the ground scatter interface and actively emit randomized radar signal to make it very hard for the reciever and its filtering routines to distinguish it from the clutter. Takes advantage of the filtering technology and the fact that only about 5% of any emitted radar signal is recieved. And also the fact that a B-52 (or 47) has lots of room and power for all kinds of fun anti radar gizmos, plus a dedicated ECM crewman.

Point is, its not just reflection angles that matter -and much of what does matter isn't being discussed.......

 

[DFW]

Point is, its not just reflection angles that matter -and much of what does matter isn't being discussed.......

Correct. However, I'm only talking about radar X-section based on shape.

IF, you really want to talk detection in space, IR is MUCH more important than radar. Basically, you can't hide a ship against a 3 K background... I could see you out to the orbit of Pluto.

 

[captainjack23]

Point is, its not just reflection angles that matter -and much of what does matter isn't being discussed.......

Correct. However, I'm only talking about radar X-section based on shape.

IF, you really want to talk detection in space, IR is MUCH more important than radar. Basically, you can't hide a ship against a 3 K background... I could see you out to the orbit of Pluto.

Exactly. A good argument as to why ships like the scout are routinely radar invisible. For most of what a ship does, either a transponder of other sensors will be relevant -radar ? Obsolete years ago for just this reason. At least as used by primitive techs (us).

 

[PFVA63]

The effect of planform alignment is to return a radar signal in a very specific direction away from the radar emitter rather than returning a diffuse signal detectable at many angles."

Correct as planes and ships are involved in a much more "2D" environment than other outer space. Ships don't have to worry about radar from underneath, planes, rarely from above, etc., etc. Reread the 1st line quoted above. THAT is only possible if you are oriented in a VERY specific way from the search radar on a consistent basis...

Hi,

I'm not sure that this is true even for a 3D space environment. Here is a qucik sketch that I did for a baseline Traveller Scout hull, as shown below.

Next, I extruded the hull out perpendicular to the main surafaces out to a distance of 5000m allowing for a 5 degree increase in size, as shown below. (I just used 5 degrees here as a reference point to show what the impact of increasing the shape size would be.

As can be seen from these images I'd suspect that if you vessel were in or near the green prisms shown you'd probably get a very strong radar return from the Scout. howeverm if I am understanding the previous links that I posted correctly, as you move away from these cones I believe that the radar relfection back will drop quickly.

Here are some other images showing the front, side and from the aft quarter, showing that there may a very large range of headings whaere the RCS of the ship may in fact be very, very low.

Anyway, just some additional info.

Regards

PF

 

[DFW]

I'm not sure that this is true even for a 3D space environment.

Yeah, it is. Here's a quick primer on the subject.

http://www.microwaves101.com/encyclopedia/Navy%20handbook/4.11%20Radar%20Cross-Section%20(RCS).pdf

 

[PFVA63]

Thanks for the link.

I kind of wasn't real clear in what I was trying to say. What I meant was where you had said;

"Correct as planes and ships are involved in a much more "2D" environment than other outer space. Ships don't have to worry about radar from underneath, planes, rarely from above, etc., etc."

and

"THAT is only possible if you are oriented in a VERY specific way from the search radar on a consistent basis..."

what I was trying to say was that even in a 3D environement like space it appears that there could be situations where the surfaces of the ship will be oriented away from a radar on a consistent basis.

Specifically if you look at the images of the Scout I posted above all major surfaces are angled very much away from the frontal aspects of the ship, as well as along the ship's forward port an starboard quarters, and above an below the aft area of the ship.

Regards

PF

 

[DFW]

what I was trying to say was that even in a 3D environement like space it appears that there could be situations where the surfaces of the ship will be oriented away from a radar on a consistent basis.

Specifically if you look at the images of the Scout I posted above all major surfaces are angled very much away from the frontal aspects of the ship, as well as along the ship's forward port an starboard quarters, and above an below the aft area of the ship.

Regards

PF

You ARE correct.

 

[GamerDude]

Besides GURPS, what books in Traveller history had excellent deck plans.

as a formerly long-time GURPS (not Gurps, its an acronym) Traveller player/GM I need to speak up on the "quality" of their deck plans.

While GURPS had a great system for figuring out how much space things took up etc, and great huge maps that you could use with 28mm minis, the deck plans in the books tend to suck in one way: Their scale was off as far as the hex grid was concerned.

Ships would have too many hexes (check the Emperess Maurava {sp} far trader. By GURPS rules it should have "X" hexes (I think 160) but when you count them up they have way too many.

Also, the key would have the iconic 'scale bar' showing how big 1m was, 3m, 6m etc. and a lable "1 hex = 1m". Measure three hexes and put it against the scale bar... it's 3.5m long.

Now the MGT ship plans for the larger ships are great as long as you don't really need to lay something out on a grid because they are just too damm big (poster blueprints like the GURPS ones would be GREAT!).

So I beseech anyone who does ship plans/layouts to remember about the scale of the grid, and have everything match up instead of driving players/gm's NUTS.

 

[GJD]

Besides GURPS, what books in Traveller history had excellent deck plans.

as a formerly long-time GURPS (not Gurps, its an acronym) Traveller player/GM I need to speak up on the "quality" of their deck plans.

While GURPS had a great system for figuring out how much space things took up etc, and great huge maps that you could use with 28mm minis, the deck plans in the books tend to suck in one way: Their scale was off as far as the hex grid was concerned.

Ships would have too many hexes (check the Emperess Maurava {sp} far trader. By GURPS rules it should have "X" hexes (I think 160) but when you count them up they have way too many.

Also, the key would have the iconic 'scale bar' showing how big 1m was, 3m, 6m etc. and a lable "1 hex = 1m". Measure three hexes and put it against the scale bar... it's 3.5m long.

Now the MGT ship plans for the larger ships are great as long as you don't really need to lay something out on a grid because they are just too damm big (poster blueprints like the GURPS ones would be GREAT!).

So I beseech anyone who does ship plans/layouts to remember about the scale of the grid, and have everything match up instead of driving players/gm's NUTS.

The Empress Marava deckplan design in GURPS was based on the one from the original CT Traders and Gunboats, which was, If I recall correctly, actually a 400 ton deckplan for a 200 ton ship.

G.

 

[GamerDude]

The Empress Marava deckplan design in GURPS was based on the one from the original CT Traders and Gunboats, which was, If I recall correctly, actually a 400 ton deckplan for a 200 ton ship.

That may be, and would explain the bad hex count..

but the size of the printed hexes not matching the scale bar in the ledgend? That has nothing to do with 400ton deckplan for a 200ton ship.

 

[GJD]

The Empress Marava deckplan design in GURPS was based on the one from the original CT Traders and Gunboats, which was, If I recall correctly, actually a 400 ton deckplan for a 200 ton ship.

That may be, and would explain the bad hex count..

but the size of the printed hexes not matching the scale bar in the ledgend? That has nothing to do with 400ton deckplan for a 200ton ship.

No, quite right.

 

[middenface]

The Empress Marava deckplan design in GURPS was based on the one from the original CT Traders and Gunboats, which was, If I recall correctly, actually a 400 ton deckplan for a 200 ton ship.

That's another ship I have fancied doing too, but different and more like the Osprey in Travellers......

 

[GJD]

The Empress Marava deckplan design in GURPS was based on the one from the original CT Traders and Gunboats, which was, If I recall correctly, actually a 400 ton deckplan for a 200 ton ship.

That's another ship I have fancied doing too, but different and more like the Osprey in Travellers......

Yeah. The 400ton version is a nice ship - suitably corridoor-y for gaming. Not sure it makes any snse as an actual working ship, but makes a nice environment for adventures.

I liked the look of the Jayhawk variant, at least externally, from TNE. It lost the B-29 style bubble canopies and seemed to be a tidyier version. I think there were deckplans in the Virus Redux adventures, but they never found there way over to these foggy shores, at least not anywhere near me.

G.

 

[Colin]

There were in the old DGP "Flaming Eye" book. I rather liked that book, if I remember correctly.

It's been awhile.

 

[Melbourne Accords]

That's absolutley right, Colin. The design was the Garu Class A2 Far Trader. It was reprinted in the DGP MegaTraveller Journal #4 (pp.58-60).

 

[spinwardpirate]

Also, the key would have the iconic 'scale bar' showing how big 1m was, 3m, 6m etc. and a label "1 hex = 1m". Measure three hexes and put it against the scale bar... it's 3.5m long.

Huh, if there is a mistake, it isn't repeated on the Scout/Courier plans. The sheet I just looked at had a scale that showed 1 hex = 1 yard, which is GURPS scale, and 1 square = 1.5m, in traditional Traveller scale. I measured the GURPS hex, and it was 1 inch across, so that looks fine too.