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typhoon prop

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Should hopefully be 4 blade, or the 3 blade with a 4 blade as a modifcation?

 

The 4 blade props were introduced in early 1944, to coincide with the larger tailplanes and the clearing of 1000lb munitions.

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4-bladed. They will chose a version which can be used from start of BoN to end of BoBP.

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35 minutes ago, Megalax said:

Should hopefully be 4 blade, or the 3 blade with a 4 blade as a modifcation?

 

The 4 blade props were introduced in early 1944, to coincide with the larger tailplanes and the clearing of 1000lb munitions.

In fact, the 4 bladed prop and Tempest tailplanes were fitted to smooth out the high-frequency vibrations that had always plagued the Typhoon...

https://forum.il2sturmovik.com/topic/54254-typhoon/?do=findComment&comment=854685

 

It was more a fortunate coincidence that Typhoons toting 1,000 lb bombs could take full advantage of the improved performance conferred by the 4 bladed propeller and Tempest tailplane (Chris Thomas: Typhoon Wings of 2nd TAF 1943-45 page 18):

 

tiffieprop003-001.jpg

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What's the performance increase with the four bladed prop? Looks like what's on ww2aircraftperformance is only data with the 3-blade prop. Also did the Typhoon get +11 boost during the Bodenplatte timeframe? I would like to know the performance in that configuration ^^

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If anything the permutations possible with 2 TAF Typhoons almost rivaled those of the Bf 109G-6: for the Normandy campaign and beyond they could be;

Bubble canopy, 3 bladed prop and bomb racks

Bubble canopy, 3 bladed prop and rocket rails

Bubble canopy, Tempest tailplanes, 3 bladed prop, bombs or rockets

Bubble canopy, Tempest tailplanes, 4 bladed prop, bombs or rockets

 

Not yet mentioned are the filters that were needed on the carburettor air intake to counter the vicious Normandy or Clavados dust (two types, with the "cuckoo door Vokes variant predominating, although the thought of having hot dome deflectors blasting across airfields would be entertaining...): there was also a tropical filter (Mod 421) that would have been in use during Bodenplatte:

 

tiffieprop005-001.thumb.jpg.ce70f5474f5df47550d18135a16c9847.jpgtiffieprop004-001.thumb.jpg.09d1c33203f2af7527ebd5369eb07428.jpgtiffieprop007-001.thumb.jpg.c1887e15f2f50ba5209a682d8808a664.jpg

 

 

Also of note is the asymmetric load-out of a 44 gallon droptank and rockets...

So, added to the list are Typhoons with carburettor filters (BoN) and/or tropical filter (BoBP)

 

 

9 minutes ago, -=PHX=-SuperEtendard said:

What's the performance increase with the four bladed prop? Looks like what's on ww2aircraftperformance is only data with the 3-blade prop. Also did the Typhoon get +11 boost during the Bodenplatte timeframe? I would like to know the performance in that configuration ^^

The main advantages with the 4 bladed propeller were improved take-off distances, initial climb rates and acceleration: it doesn't look as though the top speed changed much.

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I'd rather they go with the framed canopy. The bubble canopy obviously looks better, but the car-door style would allow us to get the Typhoon in much earlier scenarios as well, while staying historical for late-war scenarios. A good compromise would be:

 

- Car-door canopy, Tempest tailplane, and both props as a mod. This way you go from 43 to may 45.

Edited by Quinte

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1 minute ago, Quinte said:

- Car-door canopy, Tempest tailplane, and both props as a mod. This way you go from 43 to may 45.

 

All the Car-doors in service had the 3 blade and the smaller tailplanes. Car-doors were still present during Normandy but they were few and being phased out to be sent to Gloster for modification to the new bubble hood/large tailplanes/4 blade propeller.

 

The most prominent variant during Normandy was the Bubble hood with larger tailplanes and either the 3 blade or 4 blade prop.

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To me the four Hispanos matter, don't care about the prop. :)

 

On second thought, as long as there is one at all, that is.

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out of curiousity, as a person who sucks with physics and engineering.. What does a 4 bladed prop do a 3 bladed or 2 bladed does not?

Why does it seem the Germans loved 3 bladed props and never changed?

 

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You need blade area and prop area to absorb the power of the engine. All dimensions are limited due to practical and aerodynamic reasons, for instance ground clearance or blade efficiency. So at some point you can't efficiently make the prop blade longer, or you can't efficiently make it wider, but the engine power demands an increase in blade area, so you add a blade. Adding blades also costs some efficiency and adds complexity. So it's something you'll try to avoid, but it sometimes still is the best compromise.

 

Some German planes used four bladed props, such as the He177. Tribute to the power of a 3000hp engine.

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20 minutes ago, Sublime said:

out of curiousity, as a person who sucks with physics and engineering.. What does a 4 bladed prop do a 3 bladed or 2 bladed does not?

Why does it seem the Germans loved 3 bladed props and never changed?

 

I've got the same problems and the same question

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I'm thinking it's unlikely we will get more than one propeller or more than one tail. From skinning, each of those need a unique mesh and a specific section of the skin map dedicated to them.

 

It *might* be possible to have two propeller types without eating to much mesh space, but the tail section covers a lot of surface area, so I wouldn't hold out for two of them. 

 

This is the same problem the 109 has with its engine hoods, and why I'm also coming to the conclusion that we probably won't see different props as mods on the P-47 either. 

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46 minutes ago, Sublime said:

out of curiousity, as a person who sucks with physics and engineering.. What does a 4 bladed prop do a 3 bladed or 2 bladed does not?

Why does it seem the Germans loved 3 bladed props and never changed?

 

 

To add to JtD's response, a prop can be modelled in simplified way of a wing where the lift produced is the thrust. So if the lift equation is used:

Lp = 1/2*air density*Velocity^2* Prop area * Lift co-eff. (Lp=.5*rho*Vp,avg^2*Sp*CL) Note the velocity is the average velocity of the prop.

Then for thrust 

T = Power*prop-driven efficiency / Airspeed. (T=P*Eta,prop/V)

and since Lp = T

.5*rho*Vp,avg^2*Sp*CL = P*Eta,prop/V

and rearange for our prop area, Sp, we get:

Sp = (P*Eta,prop)/(.5*rho*Vp,avg^2*V*CL)

Therefore, for an increase in power,P, a larger blade area is needed. 

 

Then, as JtD said, the limitations of the blade such as ground clearance, strength and the tips going trans and super sonic etc. So you need to add more blades to make up the area

 

 

 

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Props are proportioned to the power of the engine. It swallow as much air the engine allows. Germans used very wide props. 
It is a amazing piece of engineering. 
adjustable props allows for more effective climb acceleration and cruise speed. 

Edited by No.322_LuseKofte
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1 hour ago, Voyager said:

I'm thinking it's unlikely we will get more than one propeller or more than one tail. From skinning, each of those need a unique mesh and a specific section of the skin map dedicated to them.

 

It *might* be possible to have two propeller types without eating to much mesh space, but the tail section covers a lot of surface area, so I wouldn't hold out for two of them. 

 

This is the same problem the 109 has with its engine hoods, and why I'm also coming to the conclusion that we probably won't see different props as mods on the P-47 either. 

How do the Spitfire skins go about handling the clipped vs full wing option?

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Wasn't the 4-bladed prop installed to reduce the vibration issues in the 'phoon?

 

Normally, odd-numbered props have benefits in dampening p-factor related vibrations, but there's more to vibration as the stiffness of the engine-mounts, eigenmodes and -frequencies and all other kinds of issues.

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7 minutes ago, migmadmarine said:

How do the Spitfire skins go about handling the clipped vs full wing option?

 

You skin it as a full wing. The game just removes the wingtips when you select clipped wings.

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8 minutes ago, Megalax said:

 

You skin it as a full wing. The game just removes the wingtips when you select clipped wings.

It also has a separate skin for the clipped wing tip caps. They're stored above the wing on the skins. The difference is the cap is just a thin strip of mesh. 

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2 hours ago, JG5_Zesphr said:

 

To add to JtD's response, a prop can be modelled in simplified way of a wing where the lift produced is the thrust. So if the lift equation is used:

Lp = 1/2*air density*Velocity^2* Prop area * Lift co-eff. (Lp=.5*rho*Vp,avg^2*Sp*CL) Note the velocity is the average velocity of the prop.

Then for thrust 

T = Power*prop-driven efficiency / Airspeed. (T=P*Eta,prop/V)

and since Lp = T

.5*rho*Vp,avg^2*Sp*CL = P*Eta,prop/V

and rearange for our prop area, Sp, we get:

Sp = (P*Eta,prop)/(.5*rho*Vp,avg^2*V*CL)

Therefore, for an increase in power,P, a larger blade area is needed. 

 

Then, as JtD said, the limitations of the blade such as ground clearance, strength and the tips going trans and super sonic etc. So you need to add more blades to make up the area

 

 

 

OMG MY EYES!

I told you Im terrible at the mafs

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5 minutes ago, Voyager said:

Was just looking at a screen capture of the static Typhoon in @ShamrockOneFive's article and realized we're probably going to get the same Typhoon as the staticodel: Typhoon style tail, bubble hood, and 4-bladed prop: 

https://stormbirds.blog/2019/12/14/best-guesses-at-when-hurricane-yak-9-and-first-normandy-aircraft-are-coming/

 

Possibly. They could (and maybe should) model the 3 blade version as well. For Normandy it's the three blade with bubble canopy that is most common.

 

I'm assuming we'll learn more soon!

Edited by ShamrockOneFive

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2 hours ago, Voyager said:

Was just looking at a screen capture of the static Typhoon in @ShamrockOneFive's article and realized we're probably going to get the same Typhoon as the staticodel: Typhoon style tail, bubble hood, and 4-bladed prop: 

https://stormbirds.blog/2019/12/14/best-guesses-at-when-hurricane-yak-9-and-first-normandy-aircraft-are-coming/

 

 

Not sure what you mean by "Typhoon style tail" but just to clarify for those who may not know, the late model Typhoon had Tempest horizontal tail surfaces installed. This helped give it some more authority in the pitch axis. The Tempest tail units were also less prone to flutter. 

 

Here they are as a comparison. Original Typhoon on the left, new larger Tempest Tailplanes on the right.

lJcIcMh.jpg

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@MegalaxAh thank you. I was thinking it referred to the vertical stabilizer, and was unaware it was the horizontal tail planes instead. 

 

In that case, I'm thinking the way to check would be to create a mission with the Typhoon static model on the runway, the taxi a Tempest up next to it and see if the tail planes are similar or significantly different. 

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