Stealth bird

[Big John]

Just some ramblings on stealth.

When the Air Defense Command was in high gear with Radars all over the
States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
or transponder) to located and track aircraft (we didn't think the
Russians would come in squawking for us). The FAA always used
beacon/transponder to make a large blip on their scope for traffic
control purposes.

With that background, what does FAA use today? If they do not use
'skin paint' why can't the 'glass' birds with a wooden prop, turn off
their transponder and fly through all the restricted areas unseen?

I'm not up to speed on current traffic control radar and if they both
'skin paint' and look at transponder returns?.

Anyone want to comment on this thread and expand?

Big John

[Orval Fairbairn]

In article >,
Big John > wrote:

> Just some ramblings on stealth.
>
> When the Air Defense Command was in high gear with Radars all over the
> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
> or transponder) to located and track aircraft (we didn't think the
> Russians would come in squawking for us). The FAA always used
> beacon/transponder to make a large blip on their scope for traffic
> control purposes.
>
> With that background, what does FAA use today? If they do not use
> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> their transponder and fly through all the restricted areas unseen?
>
> I'm not up to speed on current traffic control radar and if they both
> 'skin paint' and look at transponder returns?.
>
> Anyone want to comment on this thread and expand?
>
> Big John

There is still a fairly large RCS, even on a glass bird -- engine,
pilot, electronics, wiring, antennae, landing gear, etc. It would take a
lot of expertise to get the RCS down to stealth levels.

[Big John]

Orval

The only thing that reflects radar is metal or things (like paint)
that have metal in them.

The biggest contributor to the return is the engine.

WAG is that a 1 square foot flat plate might be close to equivalent
area reflecting radar if plan built?

A bird built for minimum return might even be less.

Some of the Stealth Birds are supposed to have a reflection equivalent
to a sparrow +/-. GA might get close to that with some special radar
absorbent paint, etc. ?

Big John


On Wed, 26 Nov 2003 21:35:35 GMT, Orval Fairbairn
> wrote:

>In article >,
> Big John > wrote:
>
>> Just some ramblings on stealth.
>>
>> When the Air Defense Command was in high gear with Radars all over the
>> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
>> or transponder) to located and track aircraft (we didn't think the
>> Russians would come in squawking for us). The FAA always used
>> beacon/transponder to make a large blip on their scope for traffic
>> control purposes.
>>
>> With that background, what does FAA use today? If they do not use
>> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
>> their transponder and fly through all the restricted areas unseen?
>>
>> I'm not up to speed on current traffic control radar and if they both
>> 'skin paint' and look at transponder returns?.
>>
>> Anyone want to comment on this thread and expand?
>>
>> Big John
>
>There is still a fairly large RCS, even on a glass bird -- engine,
>pilot, electronics, wiring, antennae, landing gear, etc. It would take a
>lot of expertise to get the RCS down to stealth levels.

[Big John]

Dave

Your words brought back memories. TNX. Should have remembered.

I still think homebuilders can build a Stealth bird.

Some shielding like in the 117 might be an easy way to reduce return
from areas that are not 'glass'.

Big John


On Wed, 26 Nov 2003 17:06:41 -0500, Dave Butler
> wrote:

>Big John wrote:
>
>> I'm not up to speed on current traffic control radar and if they both
>> 'skin paint' and look at transponder returns?.
>
>What you're calling 'skin paint' is what ATC calls "primary radar". The ATC
>system that processes transponder returns is called "secondary radar", also
>known as ATCRBS (Air Traffic Control Radar Beacon System).
>
>Both kinds of radar operate simultaneously and using antennas that rotate together.
>
>Occasionally you'll hear that either primary or secondary radar is out of
>service at a particular facility. If secondary radar is out of service they have
>to use some other means of identifying the primary radar returns. If primary
>radar is out of service, they can see only transponder-equipped aircraft.
>
>Remove SHIRT to reply directly.
>Dave

[Dave Butler]

Big John wrote:

> I'm not up to speed on current traffic control radar and if they both
> 'skin paint' and look at transponder returns?.

What you're calling 'skin paint' is what ATC calls "primary radar". The ATC
system that processes transponder returns is called "secondary radar", also
known as ATCRBS (Air Traffic Control Radar Beacon System).

Both kinds of radar operate simultaneously and using antennas that rotate together.

Occasionally you'll hear that either primary or secondary radar is out of
service at a particular facility. If secondary radar is out of service they have
to use some other means of identifying the primary radar returns. If primary
radar is out of service, they can see only transponder-equipped aircraft.

Remove SHIRT to reply directly.
Dave

[Gene Seibel]

Used to fly to Mexico about 20 years back in a fabric covered
Tri-Pacer without a transponder. Once, we came back into the US,
cleared customs at Bisbee, AZ and continued on to Albuquerque, NM. We
were met there by customs again, wanting to count passengers. Our leg
to Albuquerque had been very slow with a headwind and they apparently
were not sure that we had not slipped back into Mexico.
--
Gene Seibel
Hangar 131 - http://pad39a.com/gene/plane.html
Because I fly, I envy no one.



> Just some ramblings on stealth.
>
> When the Air Defense Command was in high gear with Radars all over the
> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
> or transponder) to located and track aircraft (we didn't think the
> Russians would come in squawking for us). The FAA always used
> beacon/transponder to make a large blip on their scope for traffic
> control purposes.
>
> With that background, what does FAA use today? If they do not use
> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> their transponder and fly through all the restricted areas unseen?
>
> I'm not up to speed on current traffic control radar and if they both
> 'skin paint' and look at transponder returns?.
>
> Anyone want to comment on this thread and expand?
>
> Big John

[Bob Noel]

In article >, Big John
> wrote:

> With that background, what does FAA use today? If they do not use
> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> their transponder and fly through all the restricted areas unseen?

at least some restricted areas augment the FAA radars with
primary radars that are better suited to the air defense role
than the FAA radars.

--
Bob Noel

[BTIZ]

they can still see my composite fiberglass glider with "skin paint", they
are required to watch for "primary returns" below FL180. Some aircraft are
still exempt from carrying transponders.. like balloons, gliders and J-3
cubs..

BT

"Orval Fairbairn" > wrote in message
...
> In article >,
> Big John > wrote:
>
> > Just some ramblings on stealth.
> >
> > When the Air Defense Command was in high gear with Radars all over the
> > States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
> > or transponder) to located and track aircraft (we didn't think the
> > Russians would come in squawking for us). The FAA always used
> > beacon/transponder to make a large blip on their scope for traffic
> > control purposes.
> >
> > With that background, what does FAA use today? If they do not use
> > 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> > their transponder and fly through all the restricted areas unseen?
> >
> > I'm not up to speed on current traffic control radar and if they both
> > 'skin paint' and look at transponder returns?.
> >
> > Anyone want to comment on this thread and expand?
> >
> > Big John
>
> There is still a fairly large RCS, even on a glass bird -- engine,
> pilot, electronics, wiring, antennae, landing gear, etc. It would take a
> lot of expertise to get the RCS down to stealth levels.

[BTIZ]

glass can be seen, its the square corners (wing fuse joints) and flat
surfaces (wing underside in a turn and vert fin) also reflect radar energy..
does not have to be metal..

BT

"Big John" > wrote in message
...
> Dave
>
> Your words brought back memories. TNX. Should have remembered.
>
> I still think homebuilders can build a Stealth bird.
>
> Some shielding like in the 117 might be an easy way to reduce return
> from areas that are not 'glass'.
>
> Big John
>
>
> On Wed, 26 Nov 2003 17:06:41 -0500, Dave Butler
> > wrote:
>
> >Big John wrote:
> >
> >> I'm not up to speed on current traffic control radar and if they both
> >> 'skin paint' and look at transponder returns?.
> >
> >What you're calling 'skin paint' is what ATC calls "primary radar". The
ATC
> >system that processes transponder returns is called "secondary radar",
also
> >known as ATCRBS (Air Traffic Control Radar Beacon System).
> >
> >Both kinds of radar operate simultaneously and using antennas that rotate
together.
> >
> >Occasionally you'll hear that either primary or secondary radar is out of
> >service at a particular facility. If secondary radar is out of service
they have
> >to use some other means of identifying the primary radar returns. If
primary
> >radar is out of service, they can see only transponder-equipped aircraft.
> >
> >Remove SHIRT to reply directly.
> >Dave
>

[John Harlow]

> The only thing that reflects radar is metal or things (like paint)
> that have metal in them.

> Some of the Stealth Birds are supposed to have a reflection equivalent
> to a sparrow

So, exactly how much metal is used in the construction of the modern
sparrow? ;^)

[Dale]

In article >,
Big John > wrote:

> Orval
>
> The only thing that reflects radar is metal or things (like paint)
> that have metal in them.


One of the Approach controllers I work with while flying jumpers can see
the open parachutes on the radar. There isn't much metal in a parachute
system.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

[G.R. Patterson III]

Big John wrote:
>
> Some of the Stealth Birds are supposed to have a reflection equivalent
> to a sparrow +/-.

That may be true, but I understand that some years ago they tracked a stealth
bomber completely across England based on the complaints of interference with
the cell/PSC phone service. Even as poverty-stricken as the Russian military is
these days, it wouldn't surprise me to find that they now have a cell-phone
transmission/pickup system that can track that plane real well.

George Patterson
Some people think they hear a call to the priesthood when what they really
hear is a tiny voice whispering "It's indoor work with no heavy lifting".

[Viperdoc]

Remember that props are usually metal, as well as gear legs. Also, altitude
and direction relative to the radar site also will determine the quality of
a primary return.
"Big John" > wrote in message
...
> Dave
>
> Your words brought back memories. TNX. Should have remembered.
>
> I still think homebuilders can build a Stealth bird.
>
> Some shielding like in the 117 might be an easy way to reduce return
> from areas that are not 'glass'.
>
> Big John
>
>
> On Wed, 26 Nov 2003 17:06:41 -0500, Dave Butler
> > wrote:
>
> >Big John wrote:
> >
> >> I'm not up to speed on current traffic control radar and if they both
> >> 'skin paint' and look at transponder returns?.
> >
> >What you're calling 'skin paint' is what ATC calls "primary radar". The
ATC
> >system that processes transponder returns is called "secondary radar",
also
> >known as ATCRBS (Air Traffic Control Radar Beacon System).
> >
> >Both kinds of radar operate simultaneously and using antennas that rotate
together.
> >
> >Occasionally you'll hear that either primary or secondary radar is out of
> >service at a particular facility. If secondary radar is out of service
they have
> >to use some other means of identifying the primary radar returns. If
primary
> >radar is out of service, they can see only transponder-equipped aircraft.
> >
> >Remove SHIRT to reply directly.
> >Dave
>

[Big John]

Orval

I started this thread to get some to consider going stealth.

We used to fly T-33's as target aircraft and they were very hard to
'skin paint'. To increase the size of the return, we would hang a
'Luneberg Lens' underneath the fuselage to make the radar return the
size of a B-47 'primary radar' return.

I think it would be an interesting project to make a GA stealth bird
<G>

Big John


On Thu, 27 Nov 2003 03:43:59 GMT, Orval Fairbairn
> wrote:

>In article >,
> Big John > wrote:
>
>> Orval
>>
>> The only thing that reflects radar is metal or things (like paint)
>> that have metal in them.
>>
>> The biggest contributor to the return is the engine.
>>
>> WAG is that a 1 square foot flat plate might be close to equivalent
>> area reflecting radar if plan built?
>>
>> A bird built for minimum return might even be less.
>>
>> Some of the Stealth Birds are supposed to have a reflection equivalent
>> to a sparrow +/-. GA might get close to that with some special radar
>> absorbent paint, etc. ?
>>
>> Big John
>
>It depends -- if there is a Doppler component, it can reflect radar --
>even a baseball does. Every cable, antenna, pushrod, etc. will reflect
>radar -- especially if it is multiples of quaeter-wavelengths. That is
>the principle of chaff. As I posted, it would take some effort to make
>a really stealthy plane.
>
>
>
>> On Wed, 26 Nov 2003 21:35:35 GMT, Orval Fairbairn
>> > wrote:
>>
>> >In article >,
>> > Big John > wrote:
>> >
>> >> Just some ramblings on stealth.
>> >>
>> >> When the Air Defense Command was in high gear with Radars all over the
>> >> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
>> >> or transponder) to located and track aircraft (we didn't think the
>> >> Russians would come in squawking for us). The FAA always used
>> >> beacon/transponder to make a large blip on their scope for traffic
>> >> control purposes.
>> >>
>> >> With that background, what does FAA use today? If they do not use
>> >> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
>> >> their transponder and fly through all the restricted areas unseen?
>> >>
>> >> I'm not up to speed on current traffic control radar and if they both
>> >> 'skin paint' and look at transponder returns?.
>> >>
>> >> Anyone want to comment on this thread and expand?
>> >>
>> >> Big John
>> >
>> >There is still a fairly large RCS, even on a glass bird -- engine,
>> >pilot, electronics, wiring, antennae, landing gear, etc. It would take a
>> >lot of expertise to get the RCS down to stealth levels.
>>

[Orval Fairbairn]

In article >,
Big John > wrote:

> Orval
>
> The only thing that reflects radar is metal or things (like paint)
> that have metal in them.
>
> The biggest contributor to the return is the engine.
>
> WAG is that a 1 square foot flat plate might be close to equivalent
> area reflecting radar if plan built?
>
> A bird built for minimum return might even be less.
>
> Some of the Stealth Birds are supposed to have a reflection equivalent
> to a sparrow +/-. GA might get close to that with some special radar
> absorbent paint, etc. ?
>
> Big John

It depends -- if there is a Doppler component, it can reflect radar --
even a baseball does. Every cable, antenna, pushrod, etc. will reflect
radar -- especially if it is multiples of quaeter-wavelengths. That is
the principle of chaff. As I posted, it would take some effort to make
a really stealthy plane.



> On Wed, 26 Nov 2003 21:35:35 GMT, Orval Fairbairn
> > wrote:
>
> >In article >,
> > Big John > wrote:
> >
> >> Just some ramblings on stealth.
> >>
> >> When the Air Defense Command was in high gear with Radars all over the
> >> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
> >> or transponder) to located and track aircraft (we didn't think the
> >> Russians would come in squawking for us). The FAA always used
> >> beacon/transponder to make a large blip on their scope for traffic
> >> control purposes.
> >>
> >> With that background, what does FAA use today? If they do not use
> >> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> >> their transponder and fly through all the restricted areas unseen?
> >>
> >> I'm not up to speed on current traffic control radar and if they both
> >> 'skin paint' and look at transponder returns?.
> >>
> >> Anyone want to comment on this thread and expand?
> >>
> >> Big John
> >
> >There is still a fairly large RCS, even on a glass bird -- engine,
> >pilot, electronics, wiring, antennae, landing gear, etc. It would take a
> >lot of expertise to get the RCS down to stealth levels.
>

[Steven P. McNicoll]

"Big John" > wrote in message
...
>
> Just some ramblings on stealth.
>
> When the Air Defense Command was in high gear with Radars all over the
> States and over lapping coverage, we used 'skin paint' (vs beacon/IFF
> or transponder) to located and track aircraft (we didn't think the
> Russians would come in squawking for us). The FAA always used
> beacon/transponder to make a large blip on their scope for traffic
> control purposes.
>

Not always. Radar was used by ATC for some years prior to Project Beacon in
the early sixties. Transponders didn't become the rule rather than the
exception for a few more years.


>
> With that background, what does FAA use today? If they do not use
> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> their transponder and fly through all the restricted areas unseen?
>
> I'm not up to speed on current traffic control radar and if they both
> 'skin paint' and look at transponder returns?.
>
> Anyone want to comment on this thread and expand?
>

ATC primary radar isn't all that good, especially in the Centers. Some
radar sites have beacon interrogators only, no primary radar at all. As you
say, for ATC purposes aircraft want to be seen and the vast majority have
transponders. Broadband radar provided better primary targets, but a lot of
clutter as well.

[Steven P. McNicoll]

"Orval Fairbairn" > wrote in message
...
>
> There is still a fairly large RCS, even on a glass bird -- engine,
> pilot, electronics, wiring, antennae, landing gear, etc.
>

Not on ATC radar there ain't.

[Steven P. McNicoll]

"Big John" > wrote in message
...
>
> The only thing that reflects radar is metal or things (like paint)
> that have metal in them.
>

Then how does weather radar work?

[Earl Grieda]

"Big John" > wrote in message
...
> Orval
>
> I started this thread to get some to consider going stealth.
>
> We used to fly T-33's as target aircraft and they were very hard to
> 'skin paint'. To increase the size of the return, we would hang a
> 'Luneberg Lens' underneath the fuselage to make the radar return the
> size of a B-47 'primary radar' return.
>
> I think it would be an interesting project to make a GA stealth bird
> <G>
>
I would think that just as Stealth technology has advanced over the years,
that so to has radar technology advanced. So, where in the past radar could
get a return from something size "X" now it should be able to capture and
enhance the same return from something much smaller.

Of course as greedy American corporations keep out-sourcing engineering jobs
to India and China we can soon expect those countries to start making
significant gains in military technology at our expense.

Earl G.

[BTIZ]

good question.. weather radar tracks water.. imagine that.. stronger returns
means more water means a bigger storm

we used to track migrating birds with ATC primary "skin paint".. especially
in flocks.. like the "Flying V" duck formations..

the radar was reflecting off the water in the ducks bellies.., this was
confirmed when "multiple traffic" was called to an aircraft.. "type and
altitude unknown", and the response from the pilot was... "nothing over
there but a flock of ducks heading south along the river"

BT

"Steven P. McNicoll" > wrote in message
hlink.net...
>
> "Big John" > wrote in message
> ...
> >
> > The only thing that reflects radar is metal or things (like paint)
> > that have metal in them.
> >
>
> Then how does weather radar work?
>
>

[BTIZ]

"Steven P. McNicoll" > wrote in message
hlink.net...
>
> "Orval Fairbairn" > wrote in message
>
...
> >
> > There is still a fairly large RCS, even on a glass bird -- engine,
> > pilot, electronics, wiring, antennae, landing gear, etc.
> >
>
> Not on ATC radar there ain't.
>

Funny.. local ATC calls glider traffic to the inbound airliners.. we (the
gliders) are not talking to ATC.. but they can see our glass (and metal)
birds just fine.. they just don't know our altitude.. LAS TRACON

BT

[BTIZ]

"Bob Noel" > wrote in message
...
> In article >, Big John
> > wrote:
>
> > With that background, what does FAA use today? If they do not use
> > 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
> > their transponder and fly through all the restricted areas unseen?
>
> at least some restricted areas augment the FAA radars with
> primary radars that are better suited to the air defense role
> than the FAA radars.
>
> --
> Bob Noel

They do?? mmmmmm

BT

[Steven P. McNicoll]

"BTIZ" > wrote in message
news:vVfxb.7883$ML6.4790@fed1read01...
>
> Funny.. local ATC calls glider traffic to the inbound airliners.. we (the
> gliders) are not talking to ATC.. but they can see our glass (and metal)
> birds just fine.. they just don't know our altitude.. LAS TRACON
>

Radar can be fickle.

[Cub Driver]

>With that background, what does FAA use today? If they do not use
> 'skin paint' why can't the 'glass' birds with a wooden prop, turn off
>their transponder and fly through all the restricted areas unseen?

I live in a Class D airspace. I wanted to see my house a bit closer
than 2600 ft, so I got on the handheld and asked for permission to
come down below pattern altitude. Duly granted. Then it transpired
that the controller couldn't see me. I told him my location, altitude,
and that I was circling. He told me to report at 800 feet, which I
did. But he didn't replied, and I'm not sure that he actually saw me
on the radar at any time.

J-3 Cub with metal prop.

all the best -- Dan Ford
email: (put CUB in subject line)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Cub Driver]

>I would think that just as Stealth technology has advanced over the years,
>that so to has radar technology advanced. So, where in the past radar could
>get a return from something size "X" now it should be able to capture and
>enhance the same return from something much smaller.

This is certainly true. Both the Horten Ho-229 and the Northrop YB-49
proved to be invisible to 1940s radar. I doubt they would be today.

>Of course as greedy American corporations keep out-sourcing engineering jobs
>to India and China we can soon expect those countries to start making
>significant gains in military technology at our expense.

Yes, well, I suppose we could close our borders to all trade and
re-live the 1930s. Oh, but dang it! In the 1930s it was the European
countries that made all the significant gains in military technology,
wasn't it?

all the best -- Dan Ford
email: (put CUB in subject line)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[John Harlow]

> I live in a Class D airspace.

Class D? Radar?

[Steven P. McNicoll]

"Cub Driver" > wrote in message
...
>
> I live in a Class D airspace. I wanted to see my house a bit closer
> than 2600 ft, so I got on the handheld and asked for permission to
> come down below pattern altitude. Duly granted. Then it transpired
> that the controller couldn't see me. I told him my location, altitude,
> and that I was circling. He told me to report at 800 feet, which I
> did. But he didn't replied, and I'm not sure that he actually saw me
> on the radar at any time.
>

He may not have radar at all.

[Steven P. McNicoll]

"John Harlow" > wrote in message
...
>
> Class D? Radar?
>

Some have their own, some have a scope driven by their parent TRACON, some
have none.

[Big John]

Steven

Oops. Showing my age. In my day all we had was 'pulse' radar. They now
have 'doppler' which will show the rain drops <G>

Big John

On Thu, 27 Nov 2003 04:21:26 GMT, "Steven P. McNicoll"
> wrote:

>
>"Big John" > wrote in message
...
>>
>> The only thing that reflects radar is metal or things (like paint)
>> that have metal in them.
>>
>
>Then how does weather radar work?
>

[Big John]

BTIZ

Was in a flight of two P-51's over southern Japan when ground control
asked us if we had enough fuel to intercept an unknown target?

Went 'buster' and established a rate of closure, at about three miles
distance, the target accelerated away from us and went off GCI scope.
We didn't see anything visually.

Geese?
Flying saucer?
?????????????

Came back to cruise power and after RTB debriefed. Was reported up
channels as 'Flying Saucer' even though no visual.

Big John.

On Thu, 27 Nov 2003 05:29:19 GMT, "Steven P. McNicoll"
> wrote:

>
>"BTIZ" > wrote in message
>news:vVfxb.7883$ML6.4790@fed1read01...
>>
>> Funny.. local ATC calls glider traffic to the inbound airliners.. we (the
>> gliders) are not talking to ATC.. but they can see our glass (and metal)
>> birds just fine.. they just don't know our altitude.. LAS TRACON
>>
>
>Radar can be fickle.
>

[Steven P. McNicoll]

"Big John" > wrote in message
...
>
> Oops. Showing my age. In my day all we had was 'pulse' radar. They now
> have 'doppler' which will show the rain drops <G>
>

Precipitation was shown on radar long before 'doppler' came along.