A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Military Aviation
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

V-4 Missile Possibilities



 
 
Thread Tools Display Modes
  #21  
Old January 18th 04, 12:20 PM
JasiekS
external usenet poster
 
Posts: n/a
Default


Uzytkownik "robert arndt" napisal w wiadomosci
om...
(WaltBJ) wrote in message

. com...
[snip...]

A pulsejet is a form of ramjet except that the combustion is
intermittent rather than continuous. The pulsejet uses spring loaded
shutter valves that open and close for the imtermittent pulse... but
is still a ramjet that has to be launched into the air by some means
other than the engine for it to work.


No way! They have different thermodynamical cycles! A pulsejet uses constant
volume combustion cycle while ramjet uses constant pressure combustion
cycle. Since constant volume combustion cycle is a little bit more effective
(in thermodynamical terms) then exist some rocket motors using this cycle.
Are these rockets ramjets or pulse jets?

A pulsejet motor can be started at ZERO ground speed when you supply
sufficient airstream. Once started pusejet will wor fine when you cut this
additional airstream. You can start ramjet in the same way, but when you
stop auxillary airstream ramjet will cease to work. When in high school I
attended two semesters of aeroengines. I recall one lesson when we started a
pulse jet in the way described by Keith. It took 15 min to ignite the motor
but then it worked fine. What a noise!!!

The Germans had both the As044 and Jumo 226 pulsejets under
development at the end of the war- both were investigated by the
Russians from '45-'47.

Rob


Regards
JasiekS
Warsaw, Poland

  #22  
Old January 18th 04, 04:33 PM
Kevin Brooks
external usenet poster
 
Posts: n/a
Default


"robert arndt" wrote in message
om...
Alan Minyard wrote in message

. ..
On 16 Jan 2004 22:22:15 -0800, (robert arndt) wrote:

(WaltBJ) wrote in message

. com...
Eyeballing those pictures of the As044 and the Pabst ramjet - IMHO

the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise. Its
specific fuel consumption (Kg fuel/newton/hr) must have been very

high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel (1000+
liters) for 40 minutes of sustained flight. It's climb would have been
around 17,500 fpm using the Walter rocket motor in the tail plus the
two ramjets. So you would have less than two minutes of climb to get
over the bomber stream and then dive down for the attack. I doubt the
escort fighters would have been able to do anything about it until the
Ta 283 had to land. More of the aircraft would have probably been lost
to ground accidents as the Ta 283 had very narrow track landing gear.

Rob


Well, the V-1 used the same type of pulse jet, and they were routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard


snip

Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.


Not true. Pulse jets can begin operation at zero-airspeed. Interesting photo
of one doing so on this page:

http://www.aardvark.co.nz/pjet/

I'd be reluctant to call a pulse jet a "form of ramjet", being as the latter
DOES require tremendous forward airspeed and usually relies on no external
ignition source for the development of thrust other than the compression of
the airflow.

Brooks

Rob



  #23  
Old January 18th 04, 09:15 PM
Alan Minyard
external usenet poster
 
Posts: n/a
Default

On 18 Jan 2004 01:13:30 -0800, (robert arndt) wrote:

Alan Minyard wrote in message . ..
On 16 Jan 2004 22:22:15 -0800,
(robert arndt) wrote:

(WaltBJ) wrote in message . com...
Eyeballing those pictures of the As044 and the Pabst ramjet - IMHO the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise. Its
specific fuel consumption (Kg fuel/newton/hr) must have been very high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel (1000+
liters) for 40 minutes of sustained flight. It's climb would have been
around 17,500 fpm using the Walter rocket motor in the tail plus the
two ramjets. So you would have less than two minutes of climb to get
over the bomber stream and then dive down for the attack. I doubt the
escort fighters would have been able to do anything about it until the
Ta 283 had to land. More of the aircraft would have probably been lost
to ground accidents as the Ta 283 had very narrow track landing gear.

Rob


Well, the V-1 used the same type of pulse jet, and they were routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard


Al, you must be really stupid. The pulse jet isn't dead, ever heard of
the exotic PDW (Pulse Detonation Wave) engines that have been tested
in the '90s forward? Same operation except for the fuel being ignited
by timed pulse laser.
Second, the Fw TA 283 used both a Walter rocket motor in the tail and
two Pabst ramjets which were far superior to the As014 or As044
pulsejets.
Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.

Rob


What current aircraft utilize a "pulse jet" engine??

A pulse jet is not, rpt not, a ram jet. look it up.

Sorry that your precious "ubermench" blew it. And your
dear fuhrer died.

Nazi jerk.

Al Minyard
  #24  
Old January 19th 04, 02:56 AM
robert arndt
external usenet poster
 
Posts: n/a
Default

"Kevin Brooks" wrote in message t...
"robert arndt" wrote in message
om...
Alan Minyard wrote in message

. ..
On 16 Jan 2004 22:22:15 -0800, (robert arndt) wrote:

(WaltBJ) wrote in message

. com...
Eyeballing those pictures of the As044 and the Pabst ramjet - IMHO

the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise. Its
specific fuel consumption (Kg fuel/newton/hr) must have been very

high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel (1000+
liters) for 40 minutes of sustained flight. It's climb would have been
around 17,500 fpm using the Walter rocket motor in the tail plus the
two ramjets. So you would have less than two minutes of climb to get
over the bomber stream and then dive down for the attack. I doubt the
escort fighters would have been able to do anything about it until the
Ta 283 had to land. More of the aircraft would have probably been lost
to ground accidents as the Ta 283 had very narrow track landing gear.

Rob

Well, the V-1 used the same type of pulse jet, and they were routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard


snip

Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.


Not true. Pulse jets can begin operation at zero-airspeed. Interesting photo
of one doing so on this page:

http://www.aardvark.co.nz/pjet/

I'd be reluctant to call a pulse jet a "form of ramjet", being as the latter
DOES require tremendous forward airspeed and usually relies on no external
ignition source for the development of thrust other than the compression of
the airflow.

Brooks

Rob


The Germans defined the ramjet as a propulsive duct or athodyd motor.
The As044 is defined as an intermittent propulsive duct motor
(translation: intermittent ramjet).

- from "Jane's Fighting Aircraft of World War 2"

Rob
  #25  
Old January 19th 04, 03:30 AM
Kevin Brooks
external usenet poster
 
Posts: n/a
Default


"robert arndt" wrote in message
m...
"Kevin Brooks" wrote in message

t...
"robert arndt" wrote in message
om...
Alan Minyard wrote in message

. ..
On 16 Jan 2004 22:22:15 -0800, (robert arndt)

wrote:

(WaltBJ) wrote in message

. com...
Eyeballing those pictures of the As044 and the Pabst ramjet -

IMHO
the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise.

Its
specific fuel consumption (Kg fuel/newton/hr) must have been very

high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for

fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel

(1000+
liters) for 40 minutes of sustained flight. It's climb would have

been
around 17,500 fpm using the Walter rocket motor in the tail plus

the
two ramjets. So you would have less than two minutes of climb to

get
over the bomber stream and then dive down for the attack. I doubt

the
escort fighters would have been able to do anything about it until

the
Ta 283 had to land. More of the aircraft would have probably been

lost
to ground accidents as the Ta 283 had very narrow track landing

gear.

Rob

Well, the V-1 used the same type of pulse jet, and they were

routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard

snip

Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.


Not true. Pulse jets can begin operation at zero-airspeed. Interesting

photo
of one doing so on this page:

http://www.aardvark.co.nz/pjet/

I'd be reluctant to call a pulse jet a "form of ramjet", being as the

latter
DOES require tremendous forward airspeed and usually relies on no

external
ignition source for the development of thrust other than the compression

of
the airflow.

Brooks

Rob


The Germans defined the ramjet as a propulsive duct or athodyd motor.
The As044 is defined as an intermittent propulsive duct motor
(translation: intermittent ramjet).

- from "Jane's Fighting Aircraft of World War 2"


I guess all four folks who have corrected you are somehow wrong, eh? Who
gives a rat's ass what the Germans "defined the ramjet as"? You said the
pulse jet could not be operated "until it reaches a certain airspeed"...but
the run them on test stands without a continuous pressurized air feed. "A
pulse-jet engine delivers thrust at zero speed and can be started from
rest..." (conceptengine.tripod.com/conceptengine/id17.html ), but the ramjet
does indeed require a high inlet velocity for *both* startup and continuous
operation. The ramjet has no need for moving parts--the old German pulse
jets needed inlet and outlet valves (only later would the valveless pulse
jet be developed, with little practical purpose demonstrated thus far).
Oddly enough, the pulse jet can only operate up to around 600 mph; the
ramjet can generally only operate *above* that speed. The German pulse jets,
IIRC, required an ignition source; ramjets typically do not.

Now what are all those reasons that you decided the pulse jet is a ramjet?

Brooks


Rob



  #26  
Old January 19th 04, 07:34 AM
robert arndt
external usenet poster
 
Posts: n/a
Default

"Kevin Brooks" wrote in message et...
"robert arndt" wrote in message
m...
"Kevin Brooks" wrote in message

t...
"robert arndt" wrote in message
om...
Alan Minyard wrote in message

. ..
On 16 Jan 2004 22:22:15 -0800, (robert arndt)

wrote:

(WaltBJ) wrote in message

. com...
Eyeballing those pictures of the As044 and the Pabst ramjet -

IMHO
the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise.

Its
specific fuel consumption (Kg fuel/newton/hr) must have been very

high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for

fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel

(1000+
liters) for 40 minutes of sustained flight. It's climb would have

been
around 17,500 fpm using the Walter rocket motor in the tail plus

the
two ramjets. So you would have less than two minutes of climb to

get
over the bomber stream and then dive down for the attack. I doubt

the
escort fighters would have been able to do anything about it until

the
Ta 283 had to land. More of the aircraft would have probably been

lost
to ground accidents as the Ta 283 had very narrow track landing

gear.

Rob

Well, the V-1 used the same type of pulse jet, and they were

routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard

snip

Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.

Not true. Pulse jets can begin operation at zero-airspeed. Interesting

photo
of one doing so on this page:

http://www.aardvark.co.nz/pjet/

I'd be reluctant to call a pulse jet a "form of ramjet", being as the

latter
DOES require tremendous forward airspeed and usually relies on no

external
ignition source for the development of thrust other than the compression

of
the airflow.

Brooks

Rob


The Germans defined the ramjet as a propulsive duct or athodyd motor.
The As044 is defined as an intermittent propulsive duct motor
(translation: intermittent ramjet).

- from "Jane's Fighting Aircraft of World War 2"


I guess all four folks who have corrected you are somehow wrong, eh? Who
gives a rat's ass what the Germans "defined the ramjet as"? You said the
pulse jet could not be operated "until it reaches a certain airspeed"...but
the run them on test stands without a continuous pressurized air feed. "A
pulse-jet engine delivers thrust at zero speed and can be started from
rest..." (conceptengine.tripod.com/conceptengine/id17.html ), but the ramjet
does indeed require a high inlet velocity for *both* startup and continuous
operation. The ramjet has no need for moving parts--the old German pulse
jets needed inlet and outlet valves (only later would the valveless pulse
jet be developed, with little practical purpose demonstrated thus far).
Oddly enough, the pulse jet can only operate up to around 600 mph; the
ramjet can generally only operate *above* that speed. The German pulse jets,
IIRC, required an ignition source; ramjets typically do not.

Now what are all those reasons that you decided the pulse jet is a ramjet?

Brooks


Rob


1) I only said that the pulsejet was a FORM of ramjet (primitive at
that)
2) the pulsejet is an athodyd (aero-thermodynamic-duct) motor also
since it has no compressor nor turbine
3) the V-1 had to reach 250mph off the ramp for the pulsejet to
operate independently, the V-4 with Pabst ramjet also was
ramp-launched but with a rocket pod underneath the track to get it up
to operating speed
4) main difference is only intermittent combustion vs continous
combustion, otherwise they are two stovepipe engines
5) Valveless pulsejets were experimented with after the war, another
athodyd

Rob
  #27  
Old January 19th 04, 05:37 PM
Alan Minyard
external usenet poster
 
Posts: n/a
Default

On 18 Jan 2004 17:56:31 -0800, (robert arndt) wrote:

"Kevin Brooks" wrote in message t...
"robert arndt" wrote in message
om...
Alan Minyard wrote in message

. ..
On 16 Jan 2004 22:22:15 -0800,
(robert arndt) wrote:

(WaltBJ) wrote in message

. com...
Eyeballing those pictures of the As044 and the Pabst ramjet - IMHO

the
AS044 is a pulse jet (else why the square grilled inlet?) and the
Pabst ramjet is a neat way to convert fuel into smoke and noise. Its
specific fuel consumption (Kg fuel/newton/hr) must have been very

high
indeed. I believe the ramjet fighter as pictured would have had a
range even less than that of the Me163b. (Little volume for fuel.)
Doubtless why it never made it off the sketch board.
Walt BJ

Walt,

As for the Fw Ta 283 range question: the plane had enough fuel (1000+
liters) for 40 minutes of sustained flight. It's climb would have been
around 17,500 fpm using the Walter rocket motor in the tail plus the
two ramjets. So you would have less than two minutes of climb to get
over the bomber stream and then dive down for the attack. I doubt the
escort fighters would have been able to do anything about it until the
Ta 283 had to land. More of the aircraft would have probably been lost
to ground accidents as the Ta 283 had very narrow track landing gear.

Rob

Well, the V-1 used the same type of pulse jet, and they were routinely
shot down. The pulse jet was a dead end technology.

And it is NOT a form of "ram jet".

Al Minyard

snip

Third, the pulsejet IS a form of ramjet, with intermittent combustion
vs continuous. It cannot operate until it reaches a certain airspeed.
In the Ta 283 this would be accomplished by the Walter rocket in the
tail.


Not true. Pulse jets can begin operation at zero-airspeed. Interesting photo
of one doing so on this page:

http://www.aardvark.co.nz/pjet/

I'd be reluctant to call a pulse jet a "form of ramjet", being as the latter
DOES require tremendous forward airspeed and usually relies on no external
ignition source for the development of thrust other than the compression of
the airflow.

Brooks

Rob


The Germans defined the ramjet as a propulsive duct or athodyd motor.
The As044 is defined as an intermittent propulsive duct motor
(translation: intermittent ramjet).

- from "Jane's Fighting Aircraft of World War 2"

Rob


No one cares what the Nazis called it, they lost. It was not
a ram jet.

Al Minyard
  #28  
Old January 21st 04, 04:35 AM
Bruce Simpson
external usenet poster
 
Posts: n/a
Default

On Sun, 18 Jan 2004 14:15:02 -0600, Alan Minyard
wrote:

What current aircraft utilize a "pulse jet" engine??

A pulse jet is not, rpt not, a ram jet. look it up.


You are 100% correct. Pulsejets use a completely different operating
cycle to ramjets and have significantly different operating
characteristics.

Anyone seeking further clarification can check out these pages on my
website:

http://aardvark.co.nz/pjet/ramjets.htm

and

http://aardvark.co.nz/howtheywork.shtml


--
you can contact me via http://aardvark.co.nz/contact/
  #29  
Old January 21st 04, 04:43 AM
Bruce Simpson
external usenet poster
 
Posts: n/a
Default

On 16 Jan 2004 22:11:46 -0800, (robert arndt) wrote:

A pulsejet is a form of ramjet except that the combustion is
intermittent rather than continuous. The pulsejet uses spring loaded
shutter valves that open and close for the imtermittent pulse... but
is still a ramjet that has to be launched into the air by some means
other than the engine for it to work.


Not true at all.

A properly designed pulsejet will run without forward movement through
the air and produce static thrust in the process.

The Argus V1 engine was designed to produce its maximum thrust at
around 380mph which meant that its static thrust was about half the
rated figure.

The diffuser intake system was optimized for high-speed use so the
engine was effectively somewhat choked at lower speeds.

The reason the V1 used a launch ramp was because it was a craft with a
decidedly poor power to weight ratio and a fairly high stall speed.
This was mainly due to the high fuel load required to feed that
gas-guzzling pulsejet engine.

With all that weight of fuel onboard, plus a ton of HE, there's no way
these things could have taken off under their own power in any
sensible length of runway -- and besides which, the task of keeping
them tracking straight during take-off would have required even more
complexity in their design.

A chemically powered launch ramp was a very practical solution to the
problem -- although, having said that, a goodly number of V1s crashed
reasonably close to the end of that ramp. I've got quite a bit of
interesting footage of such events.


--
you can contact me via
http://aardvark.co.nz/contact/
  #30  
Old January 21st 04, 04:46 AM
Bruce Simpson
external usenet poster
 
Posts: n/a
Default

On Sun, 18 Jan 2004 12:20:55 +0100, "JasiekS"
wrote:

A pulsejet motor can be started at ZERO ground speed when you supply
sufficient airstream. Once started pusejet will wor fine when you cut this
additional airstream. You can start ramjet in the same way, but when you
stop auxillary airstream ramjet will cease to work. When in high school I
attended two semesters of aeroengines. I recall one lesson when we started a
pulse jet in the way described by Keith. It took 15 min to ignite the motor
but then it worked fine. What a noise!!!


You are correct -- but some pulsejets don't even require forced air to
start. You can see a video of my self-starting pulsejet on my website
by clicking on the link under all the flames at
http://aardvark.co.nz/pjet/

--
you can contact me via http://aardvark.co.nz/contact/
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Australia to participate in US missile defence program David Bromage Military Aviation 40 December 13th 03 02:52 PM
AIM-54 Phoenix missile Sujay Vijayendra Military Aviation 89 November 3rd 03 10:47 PM
Poland: French Missile Report Was Wrong Michael Petukhov Military Aviation 8 October 7th 03 10:54 PM
Surface to Air Missile threat PlanetJ Instrument Flight Rules 1 August 14th 03 02:13 PM
Rafael's AIM-AIR IR Missile Countermeasure JT Military Aviation 8 July 13th 03 03:41 AM


All times are GMT +1. The time now is 08:19 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.