HDTenEightyP/NetNews huggingface dataset:
From: sherwood@fenris.space.ualberta.ca (Sherwood Botsford)
Newsgroups: sci.aeronautics
Subject: Re: Ram Jet
Date: 14 Sep 92 23:36:15 GMT
Organization: University Of Alberta, Edmonton Canada

> 
> My question is: Is/was the ramjet actually used for any
> extended period of time on any aircraft. 

I think that the Hiller Hornet used rams on the tips of  
it's main rotor. Because there was no torque, the critter  
didn't need a tail rotor assembly.  

Also didn't one of the XB-70's have auxilary ramjets?

On rams in general.  They can be designed to run at speeds  
as low as a few hundred mph.  Much depends on the shape of  
the ram.

Moving parts:  The engine itself doesn't have any.  However  
if you want to be efficient at various speeds you have to  
change the shape/position of the ram.  You also need things  
like fuel pumps, some means of extracting power for running  
that pump, cooling the ram if running at high mach numbers.   
These may well involve moving parts.

Efficiency:  Ramjets have a high fuel/sec/thrust, much  
higher than conventional turbine engines.  However they can  
run at much higher speeds.  Remember that work = force x  
distance.  An engine that is producing a 5 newtons of  
thrust at 10 meters/sec is producing 50 watts of useful  
mechanical power.  At 10000 meters/second it's producing 50  
kilowatts.  (This is not electrical power, but mechanical.)

Just as a conventional jet is inefficient when running at  
prop-plane speeds, so a ramjet is inefficient when running  
at conventional jet speeds.
Newsgroups: sci.aeronautics
Subject: Aurora propulsion
From: jim@netlink.cts.com (Jim Bowery)
Date: Sat, 05 Sep 92 18:34:43 PDT
Organization: NetLink Online Communications, San Diego CA

I've started hearing rumors that Aurora's propulsion may not be Pulse
Detonation Engines (PDEs) after all, and that it might simply be
a scram jet with the PDE being another vehicle.

--                    
INTERNET:  jim@netlink.cts.com (Jim Bowery)
UUCP:   ...!ryptyde!netlink!jim
NetLink Online Communications * Public Access in San Diego, CA (619) 453-1115
Newsgroups: sci.aeronautics
From: will@wixer.cactus.org (Bill Staniewicz)
Subject: Ram Jet
Organization: Real/Time Communications
Date: Wed, 9 Sep 92 16:57:14 GMT

Newsgroups: rec.aeronautics
Subject: Ram Jet
Distribution: world
Organization: Real/Time Communications

I was watching Wings last night and they mentioned the
testing and development of the ram jet. I think they actually
used it for some time on a F-80 (not sure if this is the right
aircraft.). The jets were mounted on the tips of the wings.

My question is: Is/was the ramjet actually used for any
extended period of time on any aircraft. Wings did mention
some advantages of the ramjet, one being that it could generrate 
almost limitless power, only limited by the strength of the airframe.
Also, very few moving parts. I wonder how the fuel consumption
compares to the ordinary jet engine and what are some other advantages
and disadvantages.

-- 
Bill
will@wixer.cactus.org

Newsgroups: sci.aeronautics
From: brndlfly@athena.mit.edu (Matthew T Velazquez)
Subject: Re: Ram Jet
Organization: Massachusetts Institute of Technology
Distribution: usa
Date: Thu, 10 Sep 1992 14:26:07 GMT

will@wixer.cactus.org (Bill Staniewicz) writes:

>I was watching Wings last night and they mentioned the
>testing and development of the ram jet. I think they actually
>used it for some time on a F-80 (not sure if this is the right
>aircraft.). The jets were mounted on the tips of the wings.

>My question is: Is/was the ramjet actually used for any
>extended period of time on any aircraft. Wings did mention
>some advantages of the ramjet, one being that it could generrate
>almost limitless power, only limited by the strength of the airframe.
>Also, very few moving parts. I wonder how the fuel consumption
>compares to the ordinary jet engine and what are some other advantages
>and disadvantages.

There was a P-80 that tested Marquardt ramjets on the wingtips for a while. I
can probably find the bureau number somewhere. 

 To date no ramjet (at least not any we know about) has operated for an
extended period as a complete or partial propulsion system. I believe it was
the X-15A2 that had a model ramjet mounted on(and accidentally dismounted from)
its ventral fin.  Recently there was a flight of a scramjet atop a soviet 
>>rocket<< to demonstrate supersonic combustion.  Recent AvLeaks tell me they
just retrieved the engine from the tundra.

 Limitless power? Hardly.  You can achieve very good fuel efficiency with a
ramjet. The catch: you have to be traveling well in excess of Mach 1 to do so.
Few moving parts is another advantage.  Since there is no compressor, you
don't need a turbine (at least not the kind that runs the compressor).  The
engine essentially becomes an airbreathing rocket.

 Anyone else with a little better knowledge of high-speed propulsion systems
care to chip in?

				-T

                                T Velazquez
                                MIT Aero/Astro
                                brndlfly@athena.mit.edu
"Crayolas are one of the few things the human race has in common."
                                -Robert Fulghum
From: thad@lever.asd.sgi.com (Thad Beier)
Newsgroups: sci.aeronautics
Subject: Re: Small windtunnel Info needed
Date: 12 Sep 92 00:38:50 GMT
Reply-To: thad@sgi.com
Organization: Silicon Graphics

Rutan, among others, has used his van or truck as a wind
tunnel.  Simply mount the object to test pretty far above or
to the side of the vehicle, and drive it down the road at high
speed.  It may not be as easy to instrument, but it does have
a lot of advantages.  The biggest is that the airflow is fairly
smooth, smoothing the air coming into a wind tunnel is
a big job, and generally is not done very well.
-- 
Thad Beier..Silicon Graphics..415)390-1028..thad@sgi.com..C-172A N7770T.....FLY!
From: drela@athena.mit.edu (Mark Drela)
Newsgroups: sci.aeronautics
Subject: Re: U-2/TR-1 air restarts
Date: 12 Sep 92 22:52:55 GMT
Organization: Massachusetts Institute of Technology


|> As I understand it, the U-2/TR-1's altitude limit is actually defined
|> by the 'coffin corner', the point at which the aircraft's critical 
|> Mach number and the stall speed come together, a function of the
|> density altitude.  The U-2/TR-1 is decidedly a subsonic aircraft and
|> flying in the coffin corner is like walking on egg shells.  If you
|> overspeed you can break the bird but if you stall you will probably
|> overspeed while trying to recover - and only a few knots separate
|> these two unpleasant scenarios.

True, but at what altitude this "coffin corner" appears depends only
on the airplane's wing loading and the maximum "ceiling parameter" = CL * M^2
which it's wing can achieve.  The U-2's cruise ceiling capability comes mainly 
from its rather low wing loading.

  Mark Drela                          First Law of Aviation:
  MIT Aero & Astro          "Takeoff is optional, landing is compulsory"
Newsgroups: sci.aeronautics
From: doug@alliant.alliant.com (Doug Bloomberg)
Subject: Small windtunnel Info needed
Organization: Alliant Computer Systems Corp.
Date: Fri, 11 Sep 1992 03:50:23 GMT


	Howdy,

	I am hoping someone could help me or point me in the right
	direction, please.

	I am toying (real seriously) of building a small wind tunnel.

	Purpose:  To test 1/4 scale wings (for stall angle and placement
	of vortex generators) and wing/fuselage junctions.

	Information needed:    How many horsepower will be needed to
	turn the propellor to simulate 100mph.  Which type of propellor
	is best?  What is the actual wind speed in the tunnel? Is it
	100 mph or something lower?  What is the best material to provide
	smoke for a smoke source?

	Is there any in publication books covering small windtunnels?
	Or, where could I get an out of pub book.


	Why:  Other than because its there and I haven't done testing
	like this before, I am building a homebuilt, kit aircraft and
	I would like to see how the standard wing performs, then add
	 the vortex generators, or leading edge cuffs to change the
	stall characteristics.  Also I would like to investigate the
	shape of the wing/fuselage junction and reflexive flap angles.

	All of this is easier in a tunnel than building it and strapping
	my butt to the seat, seeing if will work or not. I hate parachutes!

	Thanks for your help in advance,

	Doug Bloomberg   (doug@alliant.com)
	Littleton, CO

	RV-6 builder

	ps. We have Aerodynamic softwear at HQ, but 1700 miles is between
	my and it. Besides, by being a computer nerd I would rather touch 
	and trust what I am testing, particularly if I might fly a "Real" 
	plane with these mods made to it.

Newsgroups: sci.aeronautics
From: swindley@elec.uq.oz.au (Robert Swindley)
Subject: Re: Ram Jet
Organization: Prentice Centre, University of Queensland
Date: Mon, 14 Sep 1992 01:48:04 GMT


...continuing my previous message on ramjets...
  Scramjets are basically ramjets with the inlet reconfigured such that 
oblique shocks (ie shocks NOT normal to the flow .. like bow shocks on
boats) occur at the inlet. The flow behind an oblique shock may be 
supersonic, so that the airflow through the combustion chamber is 
supersonic.
   This is good because
       -  it allows jet operation up to mach 25 (NASA has tested
            (up to about mach 18 for its space plane)
       -  it allows variable configuration jets to be built
            ie ramjet to mach 4, then change configuration to
              a scramjet (and maybe SSTO)

   This is bad because (not really bad, just annoying)
       - temperatures get really quite hot
       - ever tried holding a flame in a combustion chamber
             where the flow was mach 3 ????

   The Chengster      chengm@sun.mech.uq.oz.au
Newsgroups: sci.aeronautics
From: tpickett@auspex.com (Tom Pickett)
Newsgroups: sci.aeronautics
Subject: Re: F-23 Dead?
Date: 10 Sep 92 20:25:58 GMT
Reply-To: tpickett@auspex.com (Tom Pickett)
Organization: Auspex Systems, Inc.  Engineering

In article <BuDGBo.GG2@ais.org>, draper@ais.org (Patrick Draper) writes:
> I thought that the F-15 could accelerate straight up. I read in a book once
> that it could actually surpass the speed of sound in a tru vertical climb,
> and if it was already airborne at ground level, it could beat the space
> shuttle to 50,000 feet in a vertical climb.
> 
> I read it in a book, so it *must* be true, right?

Of course it's true.  As long as no additional items are hung out on
the wings/fuselage, etc... .

Once you add drag and weight onto the aircraft it becomes considerably
more "dirty" and not as aerodynamically efficient.  An F-15 at gross
weight is not likely to have a thrust to weight ratio in excess of 1,
and therefore cannot climb vertically.  Additional degradation occurs
with added drag in the form of missles, fuel tanks allowing more than
an hours flight time, and so on.

Also don't forget that the space shuttle is very heavy and it would
logically take awhile to accelerate sufficiently to overcome its mass,
hence I suppose under ideal conditions, maybe a fighter could out
climb it, but I doubt it.  Many fighter aircraft have incredible
initial climb performance (the F-104G climbed at 70K fpm according to
Jane's), but they slow down considerably as the altitude increases.


Tom Pickett 
tpickett@auspex.com
SHO  GOZE
From: nicho@VNET.IBM.COM
Newsgroups: sci.aeronautics
Subject: Re: F-23 Dead? Nahh....
Date: 15 Sep 92 14:06:02 GMT
Reply-To: nicho@vnet.ibm.com

In <1992Sep15.102113.8569@pages.com> Bruce Henderson writes:
>The reason I like the B-2 and the F-23 is that they look absolutely badass!
  I dunno. I always reckoned that the B1 was the most evil looking
mother that ever flew.
 -----------------------------------------------------------------
               ** Of course I don't speak for IBM **
Greg Nicholls ... nicho@vnet.ibm.com or nicho@cix.compulink.co.uk
                  voice/fax: 44-794-516038
From: zap@ucscb.UCSC.EDU (ZaP!)
Newsgroups: sci.aeronautics
Subject: U-2/TR-1 air restarts
Date: 11 Sep 1992 20:29:58 GMT
Organization: The UCSC Irregular Rocketeers
Distribution: world
NNTP-Posting-Host: ucscb.ucsc.edu



	Here's a question that has held my cuirosity off and on:

	The U-2/TR-1 utilise their good glide ratios to extend range and
endurance by shutting down thier engines in flight.  What equipment is
necessary on board to ensure reliable airstarts?  Many aircraft of that
era used cartridge starters, which seem to me to be a rather risky proposition
in the air.


-Ford					Internet: zap@ucscb.ucsc.edu
					UUCP    : zap@gorn.santa_cruz.ca.us

[Insert tautology here.]


Newsgroups: sci.aeronautics
From: wayne@uva386.schools.virginia.edu (Tony Wayne)
Subject: Kite Physics Needed
Organization: Virginia's Public Education Network (Charlottesville)
Date: Wed, 16 Sep 92 02:30:34 GMT

This seems like a good place to ask this.  I'm looking for some
good sources that can describe some ot the physics in kite
flying.  A lot of what I know comes from remedial introductions
with a _little- math and a _few_ concepts.  I looking for more
so I can possible write a CAD & flight simulator.  Any
suggestions?
-Tony
From: berner@b-mrda.ca.boeing.com (Ann Berner)
Newsgroups: sci.aeronautics
Subject: Re: Live Fried Chicken (Was: Re: Birds getting sucked.)
Date: 8 Sep 92 16:55:44 GMT
Organization: Boeing Commercial Airplanes MR&D

/ b-mrda:sci.aeronautics / esmythe@atl.ge.com (Erich J Smythe) /  9:31 am  Sep  2, 1992 /
In article <1992Aug31.190839.13553@kocrsv01.delcoelect.com> c23st@kocrsv01.delcoelect.com (Spiros Triantafyllopoulos) writes:
>
>That explains the development of the 'chicken gun', a device that shoots
>(dead, thawed) chicken onto plane windshields. Makes for a messy cleanup
>but is a required part of aviation life. 
>
>Spiros

A couple of additional comments, the bird-strike tests are quite expensive
and manufacturers try to avoid them by using versions of previous (already
tested) designs.  Also, I've heard a story of a 707 that struck a 12 pound
buzzard somewhere in Africa and crashed.  This is unconfirmed hearsay, can 
anyone confirm? Supposedly it's a big negotiating process between 
manufacturers and regulators to set the weight of the birds used in the test.  

Years ago I attended a Boeing family open house that included lots of info
on birdstrike tests.  There was a video of the "shark test" that was done
for Boeing's hydro-foil.  The test involved mounting a (dead) shark of 
unknown species and weight on the roof of a station wagon, and driving it
into the boat's pontoon (at an unspecified speed).
_____________________________________________________________________________
Ann Berner						Opinions expressed are
Boeing Commercial Airplanes				mine alone; I do not
berner@b-mrda.boeing.com				speak for Boeing.
Newsgroups: sci.aeronautics
From: jem3@pyuxf.uucp (25312-mc killop)
Subject: Re: supersonic B-52's??
Organization: Bellcore, Livingston, NJ
Distribution: usa,local
Date: Wed, 9 Sep 92 11:40:38 GMT

In article <1992Sep8.190630.23535@nrcnet0.nrc.ca> sharma@nrcphy1.phy.nrc.ca (Rohit Sharma) writes:
> On the subject of B-52s, I saw one of the beasties at the CNE airshow in
>Toronto on Saturday and it was one of the most intimidating sights - 
>watching the B-52 sweep down from the clouds just next to the CN tower
>
> and I think the annoucer mentioned that it was a subsonic craft.
>
>- rohit

The BUF (Big Ugly Fellow) is definitely subsonic. I saw my first
flight of BUFs (21 in all) at a 1957 show at Andrews AFB, Maryland.
Also flying that day were 96 Boeing B-47s in flights of 3; a Boeing
P-12; a North American P-51 Mustang; and the last Boeing B-17 Flying
Fortress in the USAF. The B-17 came from Eglin Field, Florida and had 
flown to Andrews on three engines (they lost one shortly after takeoff).
The purpose of the show may explain a few things. General Hoyt 
Vandenburg was retiring as Chief of the Joint Chiefs of Staff and a
big show was called for. For those of you who have seen the 1927 film
WINGS, Vandenburg did a lot of the flying in the movie. He took
off, climbed to altitude and then ducked down in the rear seat so
he could not be seen during the filming.
Newsgroups: sci.aeronautics
From: bowers@rigel.dfrf.nasa.gov (Al Bowers)
Subject: Re: F-23 Dead?
Organization: NASA Dryden, Edwards, Cal.
	<1992Sep8.134328.5065@aio.jsc.nasa.gov>
	<CKD.92Sep8162204@loiosh.eff.org>
Date: Wed, 9 Sep 1992 19:23:32 GMT

In article <CKD.92Sep8162204@loiosh.eff.org> ckd@eff.org (Christopher Davis) writes:

>tom> == tom noyes 283-4177 <noyes@sweetpea.jsc.nasa.gov> 

> tom> The reason that the F-22 was chosen over the F-23, in my opinion,
> tom> was that the USAF let pilots have too much input into which plane
> tom> they wanted. Pilots by nature are concerned about ariel combat,
> tom> the F-22 is better suited for this purpose, with its thrust
> tom> vectoring nozzels contributing the principal advantage over the
       ^^^^^^^^^ ^^^^^^^
> tom> F-23. The F-23 better meets the USAF's RFP with the strategy of
> tom> stealth, range, and supercruise over maneuverability (if you can't
> tom> see me, you can't shoot me).`

>Well, lest we forget the lessons of Vietnam, when the F-4 had only
>missiles because "dogfighting is dead", IMHO the more agile aircraft, in
>this case the F-22, is better suited to the air superiority role.  If
>you can't turn, you can't shoot *him*.

I'd like to point out that high alpha capability and thrust vectoring
agility (whatever the hell _that_ is!  No two people can agree on
exactly what is a good agility-metric) do not negate all previous
techniques for ACM.

Speed is still life.  High alpha and thrust vectoring only help in the
final stages (low and slow) of a one v one oe few v few engagement.
in a furball (many v many) you will get you tail shot off if you get
slow enough to use high alpha!

The one area _EVERYONE_ continues to forget is that thrust to weight
is still potentially more important.  the SU-27 and the MiG-29 both
have combat gross take-off thrust-to-weight ratios in the 1.1 to 1
range (yes, at combat gross both can accelerate going straight up,
something not a single US plane can do).

one of our test pilots once commented that a higher T/W was better up
to about 2:1.  At this point he said that you felt you had `adequate'
axial agility (Ed Schnieder, SETP President, NASA F-18 HARV TVCS test
pilot).  One of our other pilots also commented that at 4:1 "it hurts,
and its the only time you feel better when the engine _QUITS_
running!" (Milton Thompson, Chief Engineer, NASA Dryden, X-15 Pilot).

--
"But the fact that a 1938 touring bodied Alfa Romeo I once had is
worth $1 million sometimes bothers the hell out of me.  It's a
personal problem."                                     -Phil Hill
Al Bowers                                 bowers@rigel.dfrf.nasa.gov
Iaido   Takamine   Hobie   Rossignol   Alfa Romeo  Ducati (DOD #900)
Newsgroups: sci.aeronautics
From: bdd0066@venus.tamu.edu (bryan duke)
Newsgroups: sci.aeronautics
Subject: Re: Small windtunnel Info needed
Date: 14 Sep 1992 20:09:00 GMT
Organization: Texas A&M University, Academic Computing Services
News-Software: VAX/VMS VNEWS 1.41

In article <1992Sep11.035023.28229@alliant.com>, doug@alliant.alliant.com (Doug Bloomberg) writes...
>	I am toying (real seriously) of building a small wind tunnel.
> 
>	Information needed:    How many horsepower will be needed to
>	turn the propellor to simulate 100mph.  

Depends on the size of the test section of the tunnel (i.e. cross
section area)

>	  What is the best material to provide
>	smoke for a smoke source?
	
Way back when I was in high school, a guy made a small wind tunnel
powered by a 1 horse electric motor.  He took up smoking (cigarettes)
and used that smoke for his testing.  He slid a _very_ small straw
through holes drilled in the side (or top, whatever) and blew the
cigarette smoke through that.
> 
>	Why:  Other than because its there and I haven't done testing
>	like this before, I am building a homebuilt, kit aircraft and
>	I would like to see how the standard wing performs, then add
>	 the vortex generators, or leading edge cuffs to change the
>	stall characteristics.  Also I would like to investigate the
>	shape of the wing/fuselage junction and reflexive flap angles.
>
If you change a design of an airplane, consult either the designer 
(who will probably discourage you from doing it) or an aero engineer and
have them study/figure the results of what you want to do.  

I say, _usually_ when you change something to lower the stall speed, it
also adds drag which lowers cruise speed and increases fuel consumption.
Unless you have to take off from a very short field (or have a thing 
for flying slow), I would recommend leaving the design how it is.

>	All of this is easier in a tunnel than building it and strapping
>	my butt to the seat, seeing if will work or not. I hate parachutes!
>
Yeah, Silk let downs are no fun.  You should also have a qualified
test pilot make the first flights of your plane.  Too often people
to do something they are not qualified for and get themselves in trouble.
BE SAFE!!

>	RV-6 builder
>
The rv-6 already has pretty good take off/landing performances.  Well,
once again, just be careful.  

Good luck
--
bryan
From: br105@cleveland.Freenet.Edu (Jeffrey A. Del Col)
Newsgroups: sci.aeronautics
Subject: B-58 Sonic Booms
Date: 5 Sep 1992 12:22:44 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: br105@cleveland.Freenet.Edu (Jeffrey A. Del Col)
NNTP-Posting-Host: slc5.ins.cwru.edu


When I lived in Cleveland in the early and mid 1960's there was a 
program of regular supersonic overflights by B-58s.  The newspapers
printed warnings and ETA's of the forthcoming boom flights. We'd sit and
watch the patio door windows flex and rattle with each boom.  I imagine the
damage claims finally put a stop to the practice.  There were ususally two
planes per mission, a couple of minutes apart as I recall.

Occasionally we'd be able to see the tiny silver dots in the sky prior to
the booms.  They must have been 35 or 40 thousand feet up on the runs.

J. Del Col
-- 
Jeff Del Col      *       "I'm never lonely,...living in my heavily      
A-B College       *   populated solitude, a harum-scarum of infinity        
Philippi, WV      *   and eternity, and Infinity and Eternity seem to          
                  *   take a liking to the likes of me." Bohumil Hrabal.       
Newsgroups: sci.aeronautics
From: dlevy@viper.engin.umich.edu (David W Levy)
Subject: Re: U-2/TR-1 air restarts
Date: Mon, 14 Sep 92 09:23:11 EDT
Organization: University of Michigan Engineering, Ann Arbor
Originator: dlevy@viper.engin.umich.edu


> 
> As I understand it, the U-2/TR-1's altitude limit is actually defined
> by the 'coffin corner', the point at which the aircraft's critical 
> Mach number and the stall speed come together, a function of the
> density altitude.  The U-2/TR-1 is decidedly a subsonic aircraft and
> flying in the coffin corner is like walking on egg shells.  If you
> overspeed you can break the bird but if you stall you will probably
> overspeed while trying to recover - and only a few knots separate
> these two unpleasant scenarios.
> 
An AWST pilot report about 10 years ago covered the U-2.  The pilot stated
that, in a turn at mission altitude, the inside wing went into stall buffet
and the outside wing went into Mach buffet.
Newsgroups: sci.aeronautics
From: amstazds@tacom-emh1.army.mil (VICIAN Theodore)
Subject: Re: Ram Jet
Organization: U.S. Army Tank Automotive Command (TACOM)
Date: Fri, 11 Sep 1992 11:50:50 GMT

SCRAMJET TRanslates roughly as Supersonic Combustion
RAMJET.  We did a little theoretical work on it when
I was at Univ. of Illinois.

Ted Vician

Disclaimer:  I don't represent the TACOM when I'm writing
here or rarely, otherwise for that matter.
:

Newsgroups: sci.aeronautics