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N17 FM - review & fixes! [BIG THANKS TO 777!]


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#41 MiG-77

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Posted 23 September 2011 - 14:10

Note: IAS at altitude 1km is 155.0km/h.

Yep, but you can read it from "HUD". Most of us have to use simple gauges which just show "slightly over 150" :D
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#42 An.Petrovich

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Posted 23 September 2011 - 14:16

I clearly understand this,
so, it's not a criticism, it's just for information.
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#43 jeanba4

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Posted 23 September 2011 - 14:18

Would it be possible to compare performances with Niueport 11 (in game, obviously) ?
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#44 MiG-77

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Posted 23 September 2011 - 14:21

I clearly understand this,
so, it's not a criticism, it's a just for information.

I know, im just kidding.
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#45 JimmyBlonde

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Posted 23 September 2011 - 14:29

The wing area also seems to be inconsistently reported, some sources put it at the store figure, 14.75M^2, and others at 15M^2 or greater

And I found this which puts it at 15.262M^2!

Image
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#46 EclecticRazor

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Posted 23 September 2011 - 18:15

Crowood - Nieuport Aircraft of World War One - Aircraft Table

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#47 EclecticRazor

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Posted 23 September 2011 - 18:17

Salamander - Illustrated Anatomy of Fighters - Nieuport 17 C1

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#48 volatile_void

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Posted 24 September 2011 - 17:06

The wing area also seems to be inconsistently reported, some sources put it at the store figure, 14.75M^2, and others at 15M^2 or greater

And I found this which puts it at 15.262M^2!

Yes, this seems to correspond with the span of the upper wing:

total wing area / upper wing span / lower wing span
14.750 sq m / 8.16 m / 7.80 m (Crowood - Nieuport Aircraft of World War One)
15.262 sq m / 8.24 m / 7.80 m (your source)
15.600 sq m / 8.30 m / 7.80 m (Henry Woodhouse - Textbook of applied aeronautic engineering)


Henry Woodhouse - Textbook of applied aeronautic engineering, 1920, pages 135-136 (http://www.archive.o...pplie00woodrich" onclick="window.open(this.href);return false;">http://www.archive.o...etails/textbook … 00woodrich):

Attached File  textbookofapplie00woodrich_0149.jpg   238.3KB   192 downloads
Attached File  textbookofapplie00woodrich_0150.jpg   333.36KB   192 downloads

Edit: The drawing and figures of the Nieuport 17 in "Textbook of applied aeronautic engineering" were also published in the "Flight" magazine, 1917, pages 889-890:
http://www.flightglo...917 - 0889.html" onclick="window.open(this.href);return false;">http://www.flightglo...com/pdfarchive/ … 00889.html
http://www.flightglo...917 - 0890.html" onclick="window.open(this.href);return false;">http://www.flightglo...com/pdfarchive/ … 00890.html
The Flight magazine article refers to the german magazine "Flugsport" as the original publisher of this data.
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#49 JimmyBlonde

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Posted 24 September 2011 - 17:14

Wow, that's a big discrepancy.
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#50 Dads1958

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Posted 28 September 2011 - 00:40

I remember reading someplace that the French N17 with a Vickers MG had the same top speed and climb as the British Lewis gun version as the extra drag of the Lewis was offset by the increased weight of the Vickers. So I hope to see data that would make it easy for 777 to give us a Lewis gun version along with a better FM. I know if wishes were horses beggars could ride.
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#51 gavagai

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Posted 28 September 2011 - 00:55

I could see them having the same climb, as the Lewis N17 would have better power:weight, but the same speed? That's hard to swallow. Small increases in weight (without additional drag) have an almost negligible impact on maximum airspeed.

See here: http://www.vansaircr...lic/rv-8per.htm" onclick="window.open(this.href);return false;">http://www.vansaircr...lic/rv-8per.htm
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#52 Dads1958

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Posted 28 September 2011 - 01:19

Still gavagai I would pay the going rate of $7.62 for a British Lewis Gun N17 with the same FM. 1 or 2 MPH/KPH in our flight models is nothing.
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#53 gavagai

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Posted 28 September 2011 - 01:33

It would probably need its own FM. Having a gun on the top wing changes a lot. I would pay for it too, but don't hold your breath.
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#54 Dads1958

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Posted 28 September 2011 - 07:12

gavagai not holding my breath but I can't help but wonder is the flight model code as is able to show the small increased drag of a lewis gun and then factor in the increased weight of a Vickers and a bit more ammo? ? Even if they did add it would we notice it? Seems that making British N17 would be alot easier for 777 then a whole new plane from scratch. I got it a Pfalz D3 (Not not a D3a Like we have now) and a Brit N17 all in one package deal. OK I know don't hold your breath.
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#55 Josh_Echo

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Posted 29 September 2011 - 01:31

I remember reading someplace that the French N17 with a Vickers MG had the same top speed and climb as the British Lewis gun version as the extra drag of the Lewis was offset by the increased weight of the Vickers.

Doesn't work that way. Weight and drag are not equivalent. Drag affects speed more than weight does; weight primarily affects climb and turn.

gavagai not holding my breath but I can't help but wonder is the flight model code as is able to show the small increased drag of a lewis gun and then factor in the increased weight of a Vickers and a bit more ammo? ? Even if they did add it would we notice it?

Of course the flight model is able to model those things! And it isn't "small increased drag." It's a big difference. Yes, it would be noticeable. (Although it would need to be modelled regardless of whether people noticed it, or we'd have an unrealistic situation.) Also, 2 MPH is a significant speed change in a Great War ship, because it's a higher percentage of the overall speed than it would be for faster aircraft.
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#56 hq_Jorri

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Posted 29 September 2011 - 06:08

Well by account of the devs, they would just need to add the components of the Lewis to the FM model and they would have a new flightmodel for it.

I doubt it's something where documented performance data comes into play, because you would need comparable data for both a French and a British Nieuport. So we would have to take the effect of the Lewis gun on the flight model for granted.
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#57 MattM

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Posted 29 September 2011 - 10:23

Doesn't work that way. Weight and drag are not equivalent. Drag affects speed more than weight does; weight primarily affects climb and turn.
That Vickers on the cowling would also cause drag though.

Overall, the question is if the Vickers gun in combination with heavier load would make the plane more draggy than a lighter N17 with Lewis gun.

Even if it would, a slightly taller or wider pilot(s head) would probably make the same difference.
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#58 ImPeRaToR

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Posted 29 September 2011 - 10:26

Good thing the Michelin guy was not a Nieuport 17 ilot :D
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#59 MiG-77

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Posted 29 September 2011 - 10:30

Doesn't work that way. Weight and drag are not equivalent. Drag affects speed more than weight does; weight primarily affects climb and turn.
That Vickers on the cowling would also cause drag though.

Overall, the question is if the Vickers gun in combination with heavier load would make the plane more draggy than a lighter N17 with Lewis gun.

Even if it would, a slightly taller or wider pilot(s head) would probably make the same difference.

I am more interested how much top wing lewis would interference top wing lift.
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#60 JimmyBlonde

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Posted 29 September 2011 - 11:30

Doesn't work that way. Weight and drag are not equivalent. Drag affects speed more than weight does; weight primarily affects climb and turn.
That Vickers on the cowling would also cause drag though.

Overall, the question is if the Vickers gun in combination with heavier load would make the plane more draggy than a lighter N17 with Lewis gun.

Even if it would, a slightly taller or wider pilot(s head) would probably make the same difference.

I am more interested how much top wing lewis would interference top wing lift.

Or maybe effective wing area as a result of the lift disturbance which might also contribute to a possible discrepancy between center of lift and its' position in relation to center of gravity.

Might also go a long way to explain why the two French sources I have quote the N.17 C1 as having a larger wing area than their English language counterparts.

Of course some English language sources could quote the larger figure if their reference aircraft conformed to the common French configuration.
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#61 gavagai

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Posted 29 September 2011 - 17:39

What about that hole that was cut into the top wing sometimes?
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#62 =Fifi=

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Posted 29 September 2011 - 19:43

What about that hole that was cut into the top wing sometimes?

Always thought about a kind of "reserved place" for the Lewis version :?
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#63 JimmyBlonde

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Posted 29 September 2011 - 21:01

What about that hole that was cut into the top wing sometimes?

Example?
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#64 =Fifi=

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Posted 29 September 2011 - 21:29

What about that hole that was cut into the top wing sometimes?

Example?

Attached File  top.jpg   48.55KB   304 downloads
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#65 JimmyBlonde

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Posted 29 September 2011 - 21:35

Probably an aircraft built for the Lewis configuration but sent to a unit who used the Vickers.
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#66 DidNotFinish

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Posted 30 September 2011 - 01:26

That's the N17 profile used in the Store.
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#67 gavagai

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Posted 01 October 2011 - 13:50

The N17 is to be adjusted soon. in its roll rate specifically.

From September 27th, 2010! :lol:
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#68 ImPeRaToR

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Posted 01 October 2011 - 14:00

Probably an aircraft built for the Lewis configuration but sent to a unit who used the Vickers.

Afaik all French N17 were built with Vickers. Not sure if the British built any themselves but those they received from the French were then converted afaik, or just left as they were. Many times N16 are confused with N17, those had the Lewis gun by default of course.
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#69 =Fifi=

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Posted 01 October 2011 - 21:59

The N17 is to be adjusted soon. in its roll rate specifically.

From September 27th, 2010! :lol:

If really so, that's fantastic news (at least for me) :P

If the roll rate is increase, turn rate could be affected positive way? :? …i hope so too.
And speed adjusted, it would be perfect to match what it meant to be :D
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#70 =Fifi=

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Posted 03 October 2011 - 00:16

Found on check six french forum:

Document from NASA (Quest for Performance: The Evolution of Modern Aircraft), N17 should have quite close maniability performances to Alb DIII…

Quote: "A comparison of the data given in table I for the Albatros D-III and the Nieuport 17 leads to some interesting speculation. Although the D-III was heavier and had more wing area and a more powerful engine than the Nieuport, the values of the wing loading and the power loading for the two aircraft are not greatly different. Furthermore, the values of the zero-lift drag coefficient and the maximum liftdrag ratio are about the same. These two aircraft can therefore be considered to have about equal aerodynamic efficiency and, accordingly, to exhibit about the same performance characteristics. In fact, the maximum speeds given in table I are about the same although the altitudes at which the speeds were measured are somewhat different. Since, for small altitude variations, the decrease in drag that accompanies the reduction in air density is about offset by the reduction in power with altitude, the speed comparison of the two aircraft in the table is valid. Values of the time required to climb to various altitudes are also about the same for the two aircraft at the lower altitudes, as shown by the data in figure 2.18; however, the climbing capability of the Albatros is clearly superior to that of the Nieuport above 10 000 feet. This plus the heavier armament of the Albatros are no doubt responsible for the generally accepted opinion that it was a more effective fighter than the Nieuport 17."

Also from mecanical studies of fighters writen by academician teacher Pyschnow in the 1968 years (chapter III "history of flying machines"):

Nieuport 17/ Albatros D V

110 cv/ 160 cv
550 kg/ 910 kg
15m²/ 21m²


Turn time for a 360° (sec): 11s/ 13.5s
r: 60 m/ 75m
v manoeuvre: 36 m/s/ 36
Cy man 1.1 / 1.1
G man 2.4 / 2.0

(i don't understand the 4 last lines :? )
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#71 gavagai

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Posted 03 October 2011 - 00:57

Where did that turn data come from Fifi? That's a great find if it was determined from the real aircraft (not a theoretical extrapolation like the quoted paragraph). Our Nieuport 17 turns slower than 11s for a 360, and our D.Va turns faster than 13.5s for a 360.

r = radius
v manoeuvre = airspeed during the sustained turn
G man = g load during the manoeuvre

Cy?

Here is RoF turn data from mig-77:

Image

I don't think the N17 is really as bad as 13s. In practice I can at least turn with the Albatros D.III and D.Va with it (human opponents), and sometimes out-turn them, but then neither of us probably had 100% fuel.

Ultimately, then, for the data you posted to be useful, we'd need to know the conditions of the aircraft when their sustained-turns were measured.
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#72 =Fifi=

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Posted 03 October 2011 - 01:05

It comes from Mister Pyschnow, from his book "history of flying machines" chapter III.
He made lot of studies apparently in the 1968 years…He was an academician and teacher, that's all i know :?

I asked the guy who posted that quote on french forum, to give me references so we could investigate more…but still no answer.
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#73 gavagai

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Posted 03 October 2011 - 03:29

I'm reading the check 6 thread. What the hell is MDV? Monte de Vol?

And Fifi, you didn't say this Pyschnow fellow was from Moscow! Perhaps the 777 team knows of him or could access his work?
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#74 =Fifi=

=Fifi=
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Posted 03 October 2011 - 03:42

What the hell is MDV? Monte de Vol?

Where? Show me!
Ah yes, from Moscow :) I forget…sorry
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#75 gavagai

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Posted 03 October 2011 - 03:46

Here:

Le N17, je l'aime bien. toujours sensible structurellement comme le N11, mais globalement moi je l'aime assez et c'est un avion sur lequel je ne trouve pas grand-chose à redire au niveau crédibilité du MDV.

duh, it's: modele de vol
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#76 Chill31

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Posted 03 October 2011 - 03:54

Yeah who knows when this little plane will get fixed. I'd love to go through each plane with AnP but I doubt that will ever happen. For example, why do the sop with camel and triplane engines fly at different rpms? Why do nieuport 17 and Fokker dr1 have different rev limits on simple gages? why is n28 such a terrible turner?

I have no answer for FM fixes anymore…
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#77 =Fifi=

=Fifi=
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Posted 03 October 2011 - 04:37

Here:

Le N17, je l'aime bien. toujours sensible structurellement comme le N11, mais globalement moi je l'aime assez et c'est un avion sur lequel je ne trouve pas grand-chose à redire au niveau crédibilité du MDV.

duh, it's: modele de vol

Yes, it's flight model in french :)
As always, some french people doesn't like it while (few) others are quite pleased with actual FM.
Anyway and unfortunatly we have to deal with it for the moment.

I have no answer for FM fixes anymore…

I hope An Petrovitch (if he gets some time) will dig into what has been done, to search, track and find some errors in N17 FM eventually…
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#78 Greywing2

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Posted 03 October 2011 - 07:31

For example, why do the sopwith camel and triplane engines fly at different rpms?..

+1
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#79 hq_Reflected

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Posted 03 October 2011 - 07:41

For example, why do the sopwith camel and triplane engines fly at different rpms?..

+1

Different prop? (just guessing)
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#80 Kwiatek

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Posted 03 October 2011 - 07:56

And why in ROF DR1 and Fokker DVIII Oberursel Ur.II give ~1400 RPMs instead 1200 RPMs?



From Prüfung, Werktung, und Weiterentwicklung von Flugmotoren by DeChamps and Kutzbach, 1921:

Oberursel (Gnôme), U.I, Netto PS 95, 1200 Uml/min, 9 124/150, 16.3 liters, 3.8:1

Oberursel (LeRhône), Ur.II, Netto 110 PS, 1200 Uml/min, 9 112/170, 15.1 liters, 5.0:1

Oberursel (LeRhône), Ur.III, Netto 145 PS, 1200 Uml/min, 11 112/170, 18.4 liters, 5.0:1
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