Jump to content


Photo
* * * * * 1 votes

Nieuport 28.C1


  • Please log in to reply
150 replies to this topic

#81 Wykletypl

Wykletypl
  • Posts: 539

Posted 01 February 2015 - 16:58

"note" It is not a B&Z, it is not a turn-fighter it is in between.

Quote: "The Nieuport 28 design was an adaptation of the concept of the lightly built, highly maneuverable rotary engined fighter typified by the Nieuport 17 to the more demanding conditions of the times."

Ekhm…

And as far as I remember, whenever in aviation a fighter is described as 'highly manouverable', it means it was at best in the turning fight.
  • 0

#82 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 01 February 2015 - 17:16

The F-4 Phantom II was also described as highly maneuverable but could not out turn the Mig 19.
  • 0

     So Long, and Thanks for All the Fish

 
 


#83 hq_Jorri

hq_Jorri
  • Posts: 14143

Posted 01 February 2015 - 17:20

However bad the N28 was at manoeuvring, it can't have been nearly as bad as the one in RoF.
  • 0

#84 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 01 February 2015 - 17:24

However bad the N28 was at manoeuvring, it can't have been nearly as bad as the one in RoF.
It's not that bad but it is a speed dependent aircraft.
  • 0

     So Long, and Thanks for All the Fish

 
 


#85 Hellbender

Hellbender
  • Posts: 3321
  • LocationMadrid, Spain (originally Brussels, Belgium)

Posted 01 February 2015 - 19:28

The F-4 Phantom II was also described as highly maneuverable but could not out turn the Mig 19.

The N28 won't turn inside an Albatros or Fokker Dr.I. Its turn radius is far too big.

We're talking about turnrate. The speed with which it completes its circle, not the radius of the circle.



Anyway, since you haven't given me any references yet regarding that bad engine, I'll provide some general references from Windsock.


Image

—–

Image

—–

Image

—–

Image

—–

Image


In short:

  • Sheds fabric, has guns that jam, catches fire, even explodes because of faulty fuel lines: YES
  • Inexperienced pilots getting jumped from above by veterans (Udet and co.) in Fokker D.VIIs: YES
  • Inferior in overall performance (at patrol altitude) to the Fokker D.VII and SS D.IV: YES
  • Unable to outmaneuver a Pfalz or a Fokker and fitted with an engine that doesn't provide power: NO
  • Universally hated by its pilots and not comparable to other RFC or Nieuport rotary fighters: NO
  • Germans that downplay their losses: maybe? ;)



Really, you need to throw me a bone here. You can't expect me to read all that and dismiss everything. Please provide me with at least one good reference that sheds light on why it (and its engine) would have been so terribly bad as you describe it to be.

It's certainly clear to me that the N28 was a dangerous machine in many respects and wasn't very forgiving with the inexperienced USAAS (just like the Camel was unforgiving). I'm with Jorri on this. However bad it was, it certainly wasn't as bad as what we have now.

If the FM had been developed as a late war turnfighter in the first place, there wouldn't have been threads doubting that it was indeed one.
  • 0

J5_Hellbender


#86 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 01 February 2015 - 20:19

This is a diagram of the Gnome 9n engine timing.
Starting at A you have ignition,(before TDC) from B you have the power stroke to C,(it is 45% of a two valve engine).Starting at C you have the exhaust stroke,the exhaust valve remains open until 115 deg. after TDC.
Now can you see why the Gnome was a poor chose and did produce the required torque of a two valve engine.

Attached Files


  • 0

     So Long, and Thanks for All the Fish

 
 


#87 Wykletypl

Wykletypl
  • Posts: 539

Posted 01 February 2015 - 20:34

This is a diagram of the Gnome 9n engine timing.
Starting at A you have ignition,(before TDC) from B you have the power stroke to C,(it is 45% of a two valve engine).Starting at C you have the exhaust stroke,the exhaust valve remains open until 115 deg. after TDC.
Now can you see why the Gnome was a poor chose and did produce the required torque of a two valve engine.

That could be said about any rotary engine.

And You want to know something funny?: According to sources from Wikipedia, the very similar type of engine was occasionally used… in Sopwith Camel. And:

"British aircraft designer Thomas Sopwith described the Monosoupape as "one of the greatest single advances in aviation"."

How are You going to explain that? Because really the more I read your posts, the more I have a feeling You are that type of a gamer the Cynical Brit talked about in his video.

And besides, when even hgJorri, the VIP of Rise of Flight, admits something is wrong with N 28's FM, then You can't just make things out and protect them like Your own independence.

That's like if You went on a crusade in the soon-to-be released game 'Verdun' to improve Chauchat's performance, while completely ignoring there's a reason why it is considered 'the worst machine gun ever designed and manufactured'.
  • 0

#88 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 01 February 2015 - 21:26

If the Gnome 9n was so great how many Camels were fitted with them?Just a few and for testing none seen combat.
Did you look at the diagram? did you understand what I was describing? A normal rotary,(two valve) has a full 180 deg. power stroke a Gnome has 85 deg. power stroke, which one makes more power?
  • 0

     So Long, and Thanks for All the Fish

 
 


#89 Hellbender

Hellbender
  • Posts: 3321
  • LocationMadrid, Spain (originally Brussels, Belgium)

Posted 01 February 2015 - 23:37

This is a diagram of the Gnome 9n engine timing.
Starting at A you have ignition,(before TDC) from B you have the power stroke to C,(it is 45% of a two valve engine).Starting at C you have the exhaust stroke,the exhaust valve remains open until 115 deg. after TDC.
Now can you see why the Gnome was a poor chose and did produce the required torque of a two valve engine.

I'll hand it to you, it's a compelling argument.

Did you come to this conclusion yourself or can I read about it more somewhere?

With a little bit of Googling I found a reproduction of an article which appeared in Over the Front about the Gnome 9N, where they say this about the torque it produced (which you claim was insufficient in spite of its high brake horsepower):

http://www.kozaero.c...ary-engine.html" onclick="window.open(this.href);return false;">http://www.kozaero.c...ook-at-the-gnoc … ngine.html

The use of the “blip” switch was discouraged because it was hard on the crankshaft, especially when blipping from full power. The crankshaft is indexed to the mounting plate by a single key and the engine’s tremendous torque would occasionally shear the key by us of the “blip” switch at high power settings. This would damage the crankshaft and destroy the engine mounting plate. Harold Hartney once wrote that the “blip” switch was almost not necessary when operating the Gnôme 9N.

  • 0

J5_Hellbender


#90 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 01 February 2015 - 23:50

The link but what I thought was important is the timing diagram. http://commons.wikimedia.org/wiki/Category:Scans_from_%27Gnome_Monosoupape_aircraft_engine_manual%27,_1917And I seriously doubt it produced 160 HP.
  • 0

     So Long, and Thanks for All the Fish

 
 


#91 piecost

piecost
  • Posts: 1318

Posted 01 February 2015 - 23:59

Power = torque x engine revolutions

Assuming that the actual torque was near the rating quoted for the type then a lower torque would suggest a higher rpm. Either way, the same horsepower. An engine with relatively high rpm and low torque might use a smaller propeller; similar to replicas with modern engines. I don't think this the case with the N28

Quote about an Original Nieuport 28C-l (clipped wing?), extracted from Flying the Old Planes by Frank Tallman

"The Gnome starts without priming (unlike other rotaries), and with a real bark. As the little lady tugs at the chocks you are sure you really have a tiger in the cowling, even if the spots don't match the camouflage. With the appearance of spattered castor oil on the leading edge of the wing we know we are oiling and consequently ready for takeoff. The temperature is 63 degrees, the altitude is 53 feet, and the wind on our nose of 11 knots. With the chocks pulled and the Gnome winding up, it's like a Clydesdale or Percheron pulling, for there is no doubt as to the old engine's raw horsepower. "
  • 0

#92 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 02 February 2015 - 00:51

My last argument then I'm done. Torque=5252xHP/RPM

Gnome 9n HP from Wikipedia HP is 160@1300 RPM 5252x160=840320/1300=646.4 ft lbs of torque
Le Rhone 9j HP from Wikipedia HP is 135@1350 RPM 5252x135=709020/1350=525.2 ft lbs of torque
Both engines have about the same bore and have the same stroke but the Gnome effectively has less than half the power stroke of the Le Rhone. How can the Gnome produce more HP and torque than the Le Rhone?
If the Gnome produced that kind of power it was braking all the laws of physics.
Believe what you will but I'm off to fly my N28 as I know it. :S!:


P.S.Post like this really does not add any thing to the discussion
That could be said about any rotary engine.

And You want to know something funny?: According to sources from Wikipedia, the very similar type of engine was occasionally used… in Sopwith Camel. And:

"British aircraft designer Thomas Sopwith described the Monosoupape as "one of the greatest single advances in aviation"."

How are You going to explain that? Because really the more I read your posts, the more I have a feeling You are that type of a gamer the Cynical Brit talked about in his video.

And besides, when even hgJorri, the VIP of Rise of Flight, admits something is wrong with N 28's FM, then You can't just make things out and protect them like Your own independence.

That's like if You went on a crusade in the soon-to-be released game 'Verdun' to improve Chauchat's performance, while completely ignoring there's a reason why it is considered 'the worst machine gun ever designed and manufactured'.

  • 0

     So Long, and Thanks for All the Fish

 
 


#93 Wykletypl

Wykletypl
  • Posts: 539

Posted 02 February 2015 - 17:56

A Pup seemed even more underpowered than N 28, and it had no difficulty outturning the Albies. So the whole talk about N 28's engine not providing enough power to sustain a turn is pretty much… pointless.

I mean, really? A full 556 kg Pup with 80 hp engine did a better job than a full 698 kg N 28 with 160 hp? This is dumb.
  • 0

#94 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 02 February 2015 - 19:53

A Pup seemed even more underpowered than N 28, and it had no difficulty outturning the Albies. So the whole talk about N 28's engine not providing enough power to sustain a turn is pretty much… pointless.

I mean, really? A full 556 kg Pup with 80 hp engine did a better job than a full 698 kg N 28 with 160 hp? This is dumb.
Just food for thought.
The Pup
Wing area——-23.6 sq.m.
Take off weight-556kg.
Wing loading—-23.264kg.per sq.m.

The N28
Wing area——-20sq.m.
Take off weight-698kg.
Wing loading—-34.9kg.per sq.m.
  • 0

     So Long, and Thanks for All the Fish

 
 


#95 Wykletypl

Wykletypl
  • Posts: 539

Posted 02 February 2015 - 20:22

Just food for thought.

Good things You did answer, mr. HillBilly. I just played RoF, the very first mission of 'Hat in The Ring' campaign on Standard Diffulty. And I had managed to beat it and score two kills. Twice.

After that, I played Quick Missions, first in just N 28 with fuel on 40 against Alb D. Va on 100 fuel, and afterwards both on 50 fuel. Again I did it twice, and by the second time I shot down Albie in less than two minutes. And I decided to record it all.

So what would you say if I try to upload the recording of the second flight here, on RoF, and by analyzing it the battle tested veterans can out point what am I doing wrong and right with this plane, that it is such a B**ch to me?
  • 0

#96 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 02 February 2015 - 20:57

I was never saying the N28 was a bad airplane,just remember keep the speed up and it is great. :S!:
  • 0

     So Long, and Thanks for All the Fish

 
 


#97 Wykletypl

Wykletypl
  • Posts: 539

Posted 02 February 2015 - 21:12

I was never saying the N28 was a bad airplane,just remember keep the speed up and it is great. :S!:


Still, maybe if I show this recording to more senior pilots, they will be able to pin point the problem.

Because if I was finally able to get that shot in a turn, then clearly I do something that handicaps me. And perhaps not only me.
  • 0

#98 1PL-Husar

1PL-Husar
  • Posts: 559

Posted 05 March 2015 - 19:15

Good talk in this video about nieuport 28 ,about 6:30 and is continued in part 2 of 6. But good to watch whole :)

 

 


  • 0

34zg6jd.jpg


#99 JoeCrow

JoeCrow
  • Posts: 4145

Posted 05 March 2015 - 21:13

A Pup seemed even more underpowered than N 28, and it had no difficulty outturning the Albies. So the whole talk about N 28's engine not providing enough power to sustain a turn is pretty much… pointless.

I mean, really? A full 556 kg Pup with 80 hp engine did a better job than a full 698 kg N 28 with 160 hp? This is dumb.

 

It is not quite as dumb as you might think. Aero engines are rated on their thrust-to-weight ratio in lbs and not horsepower for a very good reason. Unlike a land vehicle the engine has to first provide sufficient power to lift its own weight into the air. Add to that the full weight of the airframe and payload and it turns out that lift (which must be at least equivalent to weight) and drag (which increases at the square of  airspeed) consumes ~75% of the available thrust just to maintain the absolute minimum airspeed required for level flight. This means that in order to increase the airspeed beyond the absolute minimum required for level-flight the Thrust part of the Thrust/Weight/Lift/Drag equation is cubed relative to airspeed.

 

If you apply the cube-rule to the horsepower/weight ratio you mention above it turns out to be a very close call...and it also explains why an aircraft will lose airspeed in a sustained turn in direct proportion to the angle-of-bank. Don't overbank unless you are prepared to lose altitude or airspeed or both (an instantaneous turn), especially if you have an airspeed advantage.

Cheers.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


  • 0

#100 ZachariasX

ZachariasX
  • Posts: 794

Posted 07 March 2015 - 21:42

My last argument then I'm done. Torque=5252xHP/RPM

Gnome 9n HP from Wikipedia HP is 160@1300 RPM 5252x160=840320/1300=646.4 ft lbs of torque
Le Rhone 9j HP from Wikipedia HP is 135@1350 RPM 5252x135=709020/1350=525.2 ft lbs of torque
Both engines have about the same bore and have the same stroke but the Gnome effectively has less than half the power stroke of the Le Rhone. How can the Gnome produce more HP and torque than the Le Rhone?
If the Gnome produced that kind of power it was braking all the laws of physics.
Believe what you will but I'm off to fly my N28 as I know it. icon_e_salute.gif


P.S.Post like this really does not add any thing to the discussion

 

Well one thing we have to keep in mind is that fuels back then were very fast burning ones, low octane. In consequence, the engines don't really exploit the full stroke.

 

Z


  • 0

#101 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 07 March 2015 - 22:52

Well one thing we have to keep in mind is that fuels back then were very fast burning ones, low octane. In consequence, the engines don't really exploit the full stroke.

 

Z

If that was true about the "the engines don't really exploit the full stroke." why would they have long strokes?

​The compression ratio was very low compared to today's engines so the fuel charge would burn the full or near full stroke and sometimes more than full stroke,( flames from the exhaust)  


  • 0

     So Long, and Thanks for All the Fish

 
 


#102 ZachariasX

ZachariasX
  • Posts: 794

Posted 08 March 2015 - 15:27

If that was true about the "the engines don't really exploit the full stroke." why would they have long strokes?

​The compression ratio was very low compared to today's engines so the fuel charge would burn the full or near full stroke and sometimes more than full stroke,( flames from the exhaust)  

 

Low octane fuels burn "faster" more like an explosion than a controlled burning. It doesn't allow similar control over the combustion process. Low compression is a concession to this fact. Else, "knocking" is what happens due to premature ignition. Control over the combustion process allows you to build up pressure in the cylinder more slowly and burn your fuel more effociently. This is why your car runs like crap when you gas up at Arcos buying the cheap shit. Get 98 octane and your car runs well because the engine is optimized for that.

 

This is a general propperty of these fuel grades. No matter where or in what you burn them. The partial use of a stroke is even a feature of the Clerget engines (and maybe others as well) to help the fully enriched air mixture of the crankshaft not getting ignited by the hot discharged air. There are sources going in detail about that, some of them mentioned in this forum.

 

But to make it clear, I didn't say it is not possible that the monosoupape got more power through the longer stroke. Usually a longer stroke gives you torque at the cost of rpm. But if you can keep the rpm, all the merrier. But to this rule we have to be aware of design and fuel limitations of that time. That is why I think the longer stroke doesn't scale that well as it would today.

 

It is an interessting topic howewer. I think I have to give the inner workings of the N28's Monosoupape a closer look.


  • 0

#103 ZachariasX

ZachariasX
  • Posts: 794

Posted 08 March 2015 - 15:37

Actually, maybe that's it. Not every design feature is just about maximizing power. Some are a consequence of the layout of an engine. The Clerget on the Camel used only partial stroke to keep the crankshaft from exploding, while sacrificing little. Combustion is long history once the piston is halfway down. But how is with the monosoupape? Anyone has an in-detail source of that engine? I mean, If a different valve layout doesn't require you to make a trick and use partial stroke, you might as well use the full stroke and profit from the rest of the power. Then it can't be too much; else they wouldn't have sacrificed it for a greater good.


  • 0

#104 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 08 March 2015 - 15:58

Zachariasy this video is not a Gnome  monosoupape engine but it does explain the operation.

​You can see that this type of engine will not make the power of a two valve engine.The engine uses both valves as exhaust valves.


  • 0

     So Long, and Thanks for All the Fish

 
 


#105 ZachariasX

ZachariasX
  • Posts: 794

Posted 08 March 2015 - 16:24

Zachariasy this video is not a Gnome  monosoupape engine but it does explain the operation.

​You can see that this type of engine will not make the power of a two valve engine.The engine uses both valves as exhaust valves.

 

Oh, thank you for that. Very instructive. And it shows that a lot of parts are vital to proper functioning: like short exhaust stack etc.

 

And it shows that slow burning fuels (like AVGAS of today) are problematic to use with these engines. If there is a residual flame left in the cylinder once the piston trvels down far enough to uncover the inlets... oh my...

 

 

Z


  • 0

#106 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 08 March 2015 - 16:39

The rate that fuel is burned is controlled by compression ratio, low octane fuels require low compression ratios. Engines are designed to use the entire power stroke except the Gnome monosoupape engines, they use about 45% of the power stroke.


  • 0

     So Long, and Thanks for All the Fish

 
 


#107 Hellbender

Hellbender
  • Posts: 3321
  • LocationMadrid, Spain (originally Brussels, Belgium)

Posted 08 March 2015 - 16:54

This is all very interesting, but does it explain why the Nieuport climbs so well yet loses energy and elevator authority in a sustained turn, without any clues that the wing might be reaching max AoA (no bufetting or wobbling), and eventually just falls out of the sky?

 

I'm pretty much at the point of accepting that the reason why our N28 feels so crap in general, is largely due to how insanely overmodeled the Albs are, who lose almost no energy at all in a turn, even at maximum elevator deflection, as I've demonstrated in the other thread about the D.Va. I still want to understand the logic behind the N28 being unable to use its climbing power to at least match the SE5a in rate of turn (which is what I would expect from it, nothing more).


  • 0

J5_Hellbender


#108 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 08 March 2015 - 16:58

 

 

loses energy and elevator authority in a sustained turn

It's called a stall.


  • 0

     So Long, and Thanks for All the Fish

 
 


#109 Hellbender

Hellbender
  • Posts: 3321
  • LocationMadrid, Spain (originally Brussels, Belgium)

Posted 08 March 2015 - 17:15

It's called a stall.

 

Very laconic, but you'll have to be more specific.

 

A normal stall or an accelerated stall? A normal stall would surprise me, as I'm quite far removed from the N28's stall speed.

 

As for an accelerated stall, which is much more likely (expected even, and currently present on all the planes in RoF when turning with full elevator deflection, except the Albatros series), shouldn't there be effects accompanying it (buffeting etc.)?


  • 0

J5_Hellbender


#110 ZachariasX

ZachariasX
  • Posts: 794

Posted 08 March 2015 - 17:30

The rate that fuel is burned is controlled by compression ratio, low octane fuels require low compression ratios. Engines are designed to use the entire power stroke except the Gnome monosoupape engines, they use about 45% of the power stroke.

 

Exactly. The rate fuel is burned depends on compression ratio... AND on fuel grade. This is why you can use 110 octane for your car, but you hurt the engine when using 75 octane. Higher fuel grade *allows* higher compression, it doesn't require it. But low octane *requires* low compression, else it detonates, "knocks".

 

True, it is silly not using fullpower stroke, unless you have a good reason to. With the Gnome, they discarded half of the stroke, but they didn't lose half the power. Thus, my original argument, I would *guess* based on that, that increasing the stroke increases power only marginally in such engines.

 

Z


  • 0

#111 Plank

Plank
  • Posts: 2835
  • LocationNew Zealand.

Posted 20 April 2015 - 03:35

Gentlemen.

 

It would be a shame to let this debate cool off.

 

In the N.28 with pretty much anything on my tail I am dead meat.

 

And I would like t know why.

 

at 203 kph. it should swerve through the air like a maniac and be able to avoid fire and eventually out run it's tailing slower fatter annoyance.

 

If it's  gutless engine can propel it to a good chop then the air frame itself is not letting the side down.  ( in my mind of course)

 

It feels good.

it feels a bit too stable.

It's not at agile as I would expect.

 

It seems to have something jammed in the controls... 

 

and I don't care if the fabric tears off. Let it!

 

Plank. (planking near a thread close by...)


  • 0

-

Captured again!

 


#112 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 20 April 2015 - 12:25

 

 

In the N.28 with pretty much anything on my tail I am dead meat

It is the unrealistic long range shots in ROF that accounts for most of my defeats in the N28,( ranges from 350 m to over 500 m).

Remember what Andy Jackson said at the battle of New Orleans ?


  • 0

     So Long, and Thanks for All the Fish

 
 


#113 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 20 April 2015 - 13:00

@ ZachariasX on the fuel grade used by all engines back then was about 45-55 octane.

Now lets look at the difference in the Gnome 9n and a two valve engine.

 

The Gnome, we will start at the intake stroke, the exhaust valve is open, as the piston moves down it is drawing air in until about 2/3 stroke then closes.

The piston continues to move down drawing a vacuum, as the piston uncovers the intake ports a fuel rushes in,(now the interesting part) as the piston starts back up some fuel is forced back to the crankcase. The results is the cylinder is not fully charged.

 

The two valve engine, the intake valve is open and the piston is moving down until it gets close to the bottom of stroke then the intake valve closes, a full cylinder charge.  


  • 0

     So Long, and Thanks for All the Fish

 
 


#114 ZachariasX

ZachariasX
  • Posts: 794

Posted 20 April 2015 - 13:28

@ ZachariasX on the fuel grade used by all engines back then was about 45-55 octane.

Now lets look at the difference in the Gnome 9n and a two valve engine.

 

The Gnome, we will start at the intake stroke, the exhaust valve is open, as the piston moves down it is drawing air in until about 2/3 stroke then closes.

The piston continues to move down drawing a vacuum, as the piston uncovers the intake ports a fuel rushes in,(now the interesting part) as the piston starts back up some fuel is forced back to the crankcase. The results is the cylinder is not fully charged.

 

The two valve engine, the intake valve is open and the piston is moving down until it gets close to the bottom of stroke then the intake valve closes, a full cylinder charge.  

 

Interessting aspect, yes you do get the full stroke. But How much power do you get from the additional travel when the fuel is already burned up and all you're having now is just the gas pressure from before? Does that that scale well?


  • 0

#115 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 20 April 2015 - 14:09

Interessting aspect, yes you do get the full stroke. But How much power do you get from the additional travel when the fuel is already burned up and all you're having now is just the gas pressure from before? Does that that scale well?

The point is that the fuel is not all burned up at half stroke in a two valve engine.


  • 0

     So Long, and Thanks for All the Fish

 
 


#116 ZachariasX

ZachariasX
  • Posts: 794

Posted 20 April 2015 - 19:47

The point is that the fuel is not all burned up at half stroke in a two valve engine.

 

Why should there be a difference in fuel burning speed given comparable octane level and comparable compression?


  • 0

#117 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 20 April 2015 - 19:56

Why should there be a difference in fuel burning speed given comparable octane level and comparable compression?

It is not the burning speed, it is the amount being burned.


  • 0

     So Long, and Thanks for All the Fish

 
 


#118 Plank

Plank
  • Posts: 2835
  • LocationNew Zealand.

Posted 20 April 2015 - 21:28

Report No 001

AC: N.28

Pilot: "Plank"

 

>Basic:

 

The plane handles very well.

Controls respond positively.

Stable and very easy to fly.

Quite fast and good traction level flight.

Quite deft and confidant.

Can dive.

 

Cannot climb.

Cannot sustain any manoeuvre  ( 1/4 S at best before critical energy loss. )

Easily damaged by enemy fire.

 

 

>Attacking strategy: (solitary predation )

 

Attack from behind.

Attack an AC that is not aware of your presence

Telescope your attack to coincide with predicted enemy path. (fly straight do not turn)

Attack hard. (constant accurate fire do not let up)

Disengage Immediately after attack

 

note: A fast diving attack will reduce "in range" time significantly.

 

 

 

>Disengaging.

 

Shallow dive away (do not turn or attempt to dive steeply )

Use cover.

Radiate away from enemy. (Reduce silhouette)

Do not return to engage if followed.

 

Note: Maintain max IAS at all time.

 

 

>Major fault:

 

Extreme energy loss.

 

 

>Warning signs of energy loss:

 

Dramatic reduction of engine note.

Loss of IAS

 

 

 

> Remedial action:

 

Immediately replace power plant.

AC is significantly underpowered.

 

note: Ac will produce good results if it can sustain a fast smaller turn.

 

 

 

My opinion:

 

Kills by N.28 require skill and strategy from veteran pilots which would be wasted on this AC.

Continuous attacks by waves of N.28's could succeed but only under excellent conditions.

This could be a waste of higher pilot skill and the required daring.

 

The plane itself is essentially sound and is very easy to fly.

 

It has punch but no follow up at all.

 

It is wildly underpowered.

 

Plank.


  • 0

-

Captured again!

 


#119 =HillBilly=

=HillBilly=
  • Posts: 5605
  • LocationSouthern Ozark Mountains

Posted 21 April 2015 - 02:49

Plank I think you are starting to get the N 28, just one point,(Disengaging) try to pull up and turn away from their turn, stay on top.


  • 0

     So Long, and Thanks for All the Fish

 
 


#120 ZachariasX

ZachariasX
  • Posts: 794

Posted 21 April 2015 - 07:05

It is not the burning speed, it is the amount being burned.

 

This implies that you consider the monosoupape with it's partial stroke a "smaller displacement" engine (less de facto cubic) than the two valve variant using full stroke (as they have all about similar compression ratio)? I'm asking that because the amout of fuel you add is just dependent on the amout of air the enigne "pumps". You cannot change really the fuel/air mixture too much. Lean/rich mixture is a subtle change in mixture.

 

If you lost 50% of the stroke that way and that would translate into 50% less de-facto displacement of the engine you get 50% of the power. I serouisly doubt they'd happily made a monosoupape arrangement at that performance penalty.


  • 0


0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users