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First time Juke
03-19-2007, 06:57 AM
I just figured a pretty straight forward engine type to propel the future racers at pretty cheap price.

Two V-8s back to back propelling a contra prop ? Would that be enough power to make a ( very ) small racer go 500 mph + ?

:feedback:

First time Juke
03-19-2007, 07:42 AM
Those F-1 car engines do 800 ps a piece...so 1600 hp..in a very compact size ( and weight ) + small consumption...right reduction and voila....perhaps a perfect ( torque free ) engine for an unlimited racer.

AirDOGGe
03-19-2007, 10:06 PM
The F1's get their power by using small displacement engines turning at incredibly high RPMs. Can you imagine what a super-sport plane would sound like with the powerplant doing 14,000 rpm's? Would the high ratio reduction gearing necessary to get the rpms down to prop speeds handle the vibrations?

In addition, a tandem is sending the power from the rearmost engine through the crankshaft of the front one. You think controlling torsional vibrations of a single crank is bad? Try two of 'em.

But I guess a tandem can be done. The Macchi MC-72 (world's fastest seaplane) used a tandem V-12 arrangement, didn't it?

(Googling...)

Yep. Here it is, complete with a picture of the engine(s). I don't know if they shared a common crankcase or crankshaft though.

http://www.aviationtrivia.homestead.com/MC72.html



.

mary robey
03-19-2007, 11:53 PM
Didn't the XP75 Eagle by Fisher Body {GM} have contra props with 2 V12 Allisons behind the pilot. Lots of problems but it did fly at the Cleveland,Ohio airport during testing.
Mary

First time Juke
03-20-2007, 12:47 AM
Heinkel He-119 and He-177 Greif had also paired engines.

http://en.wikipedia.org/wiki/Heinkel_He_177

I think two V-8s would be way smaller in space need than twin V-12s ...the angle in the V form is decisive here..even if their proportional size was the same.

Seems that the DB-610 overheated quickly and gearbox troubles in the one prop system were common.

Also Napier Sabre was a 24 cylinder engine but an H-type..also prototypes of that overheated quikly.

Those are the problems that has to be solved.

What I see as a big advantage is that if one engine looses a piston the other keeps going..those engines and a prop would be a unit of their own..albeit being close together..this has never been even tested before..as far as I know. Maybe it is not as problematic as those predecessors in the first place ?

First time Juke
03-20-2007, 01:30 AM
The F1's get their power by using small displacement engines turning at incredibly high RPMs. Can you imagine what a super-sport plane would sound like with the powerplant doing 14,000 rpm's? Would the high ratio reduction gearing necessary to get the rpms down to prop speeds handle the vibrations?

In addition, a tandem is sending the power from the rearmost engine through the crankshaft of the front one. You think controlling torsional vibrations of a single crank is bad? Try two of 'em.

But I guess a tandem can be done. The Macchi MC-72 (world's fastest seaplane) used a tandem V-12 arrangement, didn't it?

(Googling...)

Yep. Here it is, complete with a picture of the engine(s). I don't know if they shared a common crankcase or crankshaft though.

http://www.aviationtrivia.homestead.com/MC72.html



.

AirDOGGe,

Thanks for your input.

I am not talking about tandem configuration.

One V-8 would be turning a smallish 2 bladed prop and the other also geared through a reduction almost similar ( mirror image ) size prop to opposite direction. It would naturally have to be vibration free. Gearbox ( reduction but no box ? ) would also have to be really close to the paired engines ( if not partially in between them ). This is the task also..to make it dependable and vibration free. At least firewall can be sturdy in size albeit not as huge as in a single Merlin.

RPMs would be naturally awful high and noisy..possibly a neat muffler can be introduced as and if the project would go on. Also the engine might be tuned for lower rpm and having more torque...reduction would be in any case adjusted to the right prop rpms.

First time Juke
03-20-2007, 03:57 AM
I was searching the internet..and one dude was about to make himself a flat V-8 for a car to avoid vibrations...I think a pair of those would be ok ?

More about V-8s here;

http://en.wikipedia.org/wiki/V8



A Mopar Hemi produces 425 hp and 850 hp doubled..without enhancing..not bad. Used in Corvette etc.

First time Juke
03-20-2007, 10:18 AM
Next I'll try to prove why a pair of smaller V-8s could be better than a RR Merlin V-1650




http://www.unlimitedexcitement.com/Pride%20of%20Pay%20n%20Pak/Rolls-Royce%20Merlin%20V-1650%20Engine.htm

Rolls-Royce V-1650-9 specs from the insert;

Weight 1,690 lbs
Power 1735 bhp @ 3000 rpm 66" boost




Here is the RS27 V8 by Renault

http://www.sportnetwork.net/main/s208/st110829.htm

Weight 211 lbs
Power 800-950 bhp @ 14000-23000 rpm



Ok let us say for aeroengine a 750 hp would be enough to be on the safe side.

Lets make a small Do-335 type pull push design ( original flew 775 km/h~481 mph ) cleaner without guns etc ( clean could mean a supercharger airintake in the spinner through a hole in the prop shafts for the front engines..for instance). Two engines at the back and two at the front weighing 844 lbs and producing 2800 hp.

This is 1000 hp more at more than half the weight compared to boosted RR V-1650 !

A tractor layoyt racer could have two of these units in tandem..with same power output and weight, but with just one unit 422 lbs and 1500 hp.

Tractor layout kite with this engine unit would hardly weigh more than 2000 lbs..this would yield an unheard power to weight ratio of 1,6 kg / hp. It would be nearly triple of any WW II fighter and double of any regular piston racer up to now.

At 3000 lbs racer it would be 1,1 kg/hp, thus almost double power to weight ratio of the Heinkel He-100 V8 of 1939 which did 460+ mph.
Ernst Heinkel estimated he could make a piston fighter to go 545 mph at 0,8 hp/kg.

Even @ 600 hp per V8 and weighing 4000 lbs this new kinda lite racer would beat Heinkels last 545 mph mover by 10% in power to weight ratio vise.



Ok any comments on this please ? :feedback:

h34race
03-20-2007, 11:31 AM
Hey the falconer v12 is already to do what is needed and I think it has 1200hp injected and that is a mild version just wanted to put my two cents,I wish thay would test more diesel power already make big HP and torque at low rpm I just don't know if thay make a light enough verison to make the CG work any alum diesels out there?? thanks

First time Juke
03-20-2007, 11:44 PM
There is indeed Falconer V-12 and a Thunder Mustang to prove that small size goes a long way.

Falconer produces 640 hp and weighs 980 lbs with prop and reduction + other gizmos.
http://www.thundermustang.com/falconer.htm

2x8 is sixteen and 2 x 800 hp is 1600 hp..it is 1/4th ( 960 hp without injection ) more than Thunder Mustangs Falconer. Older V10 F1 car engines were close to 1000 hp, but they blew often with a large fireball..no one wants that to happen in the air.

I am pretty sure with all reduction and prop etc this paired V-8 is close to 800 lbs with firewall and other gizmos. That CG point is very good also.

I guess this could be a dead end. Just food for the thoughts anyway. :rolleyes:

First time Juke
03-21-2007, 12:21 AM
Thunder Mustang gross weight is 3200 lbs and with 640 hps it gains a 0,44 hp/kg power to weight ratio. Pretty close to average WW II piston fighter.

This is the fastest kit plane and a remarkable achievement as such.

http://www.thundermustang.com/index.html

First time Juke
04-05-2007, 08:28 AM
Hi !

Since several folks seem to have been interested about this 2 x V8 subject. I like to add little bit more.

Anybody know if it is ok to slant a V8 90 degrees ?

If it is ok then what can one install between the l l positioned V8 engine blocks ?

Damn right a nose gear could be housed there...and you have a tricycle landing gear, which means better visibility in taxiing etc.

Any interest on this ? :feedback: or is this totally :OT-2: ?



Happy Easter !



rgds,

Juke

Stevey
04-08-2007, 01:55 PM
Hey, I'm new to this board but have been designing a plane for the reno air races for the last few years. I doubt it will ever happen as I dont have the money to make something like that happen. But I was going for sports class. I see your going for unlimited. I dont know much about airplane engines, Im a car engine kinda guy. Are there carbureted airplanes? If so why not run a supercharged 572 cubic inch hemi? Dump some money into it and you can get some crazy high power without having to have a lot of rpms. Having said that you would still have to have a gear reduction I'd imagine. If Im correct the average propeller can only make thrust up to about 7000rpm then the tips of the blades attempt to go supersonic. You should have no problem making the same amount of power as some of those WWII fighters. Although you may have to go up in the 600's for cubic inches. Then the engine will also be quite simple to work on in comparison to some of the other fuel injected "wonders" of today. Ill give what you said a few more thoughts and see what I can actually come up with. Are you just toying around or is this something youd actually like to build? I dont understand where people get the money to air race but it must be quite a wealthy comunity {no offence meant just a jealous observation}, please let me in on your secrets lol.

Steve

First time Juke
04-12-2007, 12:10 PM
Stevey,

Quite frankly; I think there has to happen a small scale miracle before I get the backing for this kite for real.

At one stage a gentleman from Norway offered two unused Mossie engines still in wraps for the TS II ( pic in my avatar ), but not for free.

There was an excellent prototype for this kinda racer..the Tsunami...with a V tail and tricycle and double independently turning Hemis ( or what ever flat v-8s ) I think this ( still smaller than a Tsunami ) might really have a change to brake 540 mph mark.

Plane doing these speeds and me being 44 years old...I think I might run out of time before any of my planned plane gets a change to fly.

These for now are pure fantasies for me, but you never know, if some sugardaddy with lotsa spare money appears on the scene like Randy " Hacker " Haskin once put it.

With two Hemis this would be more in the reach than the Merlin racer I have been dreaming/designing between 1989-2003. I mean lighter engine putting the same if not more hp:s..what else does one need...for an idea..to overcome a obstacle..in order to reach the goal of piston engined racer absolute speed record.

Stevey...are you sure a single Hemi would propel a man beyond 540 mph ? Rare Bear had 4500 hp:s to go 528 mph. With an inline engined kite you'll definitely need more than 1/1 hp/kg still. It would have to be nearly Bede sized rocket !

I think I am still doing this to keep myself sane...like some do crosswords...you know what I mean ? :rolleyes:

I would have to employ a real phd aerodynamist to work with me, a pilot, an outstanding crew to build the plane and tune it and a windtunnel + 5 years and 20 million dollars to do it...I miss all of that, but they exist somewhere around this tube that I am staring at.

Eric A. has same dream with his pusher...the Dart...will any of these ever fly... I hope so.

Stevey
04-12-2007, 03:07 PM
Well thats what I was wondering, where does everyone come up with the money? I had an offer to fund me for my sport class IF I built the plane myself. In other words hed pay for materiels, at the time I was younger and wouldnt take on such a project. If I knew if the offer was still open I may have reconsidered. The porblem is, it's basically impossible to make the money back and it ends up being a big hole for money. Unless you were to make a small scale company building the aircraft {as 5 need to be built for sport class}. Even then you would have to sell a lot of aircraft to get your money back!

I dont believe it would cost me that much to build this plane and get it in the sky and operating BUT the problem would be the fact that I would have to build at least 5 air frames, eerrr "kits". The plane I have been designing seems to have a good chance at some very high speeds, I have started building models to put in a minature wind tunnel I built along with bigger models to fly as an rc plane. Hopeing this will bring to light any aerodynamic problems.

Sorry, Im stealing your thread. I do believe a single engined aircraft with a high displacment hemi could propel AN aircraft to 540mph. But I know it wouldnt be able to propel something the size of Rare Bear to 540mph. If you are planning on unlimited class {not sure minimum weight?}, you could continue with your plan. Or you could follow the trend and drop one huge powerplant up front. Personally Id try and exhaust all of the "normal" forward mounted engine possibilities simply because its tried tested and true. You wont know any possible aerodynamic effects of having 2 props until you try it and by that point it may be too late. My approach has always been 1} Lower as much drag as possible 2} Drop as much weight as possible 3} Make as much power as possible. I have never looked into any radical air frame changes as you are considering. Having said that though, You may be on the right track as there are always some type of technilogical breakthrough's when people go off the beaten trail. I do know that some hemi's in funny car's CAN make up to 2600hp, but I cant imagine they are the most reliable engines in the world. What weight would you be looking at? What hp to kg ratio? What class? Unlimited?

I do believe your goal can be achieved but if I were you I wouldnt be looking for a pilot, crew, aerodynamicist etc. If you are honest to god serious I would get my pilots licence {if I didnt already have them}, it will teach you alot about plane characteristics etc and youll be able to get in flying time {some places rent airplanes for lessons or just logging hours, no need to buy one} and by the time your finished your plane youll be ready to get in the cockpit. Then Id look into taking an online course in aerodynamics {assumeing you dont already have one}, you can take it on your own time it costs minimal $$ and youll learn alot. You will then be able to come up with the piliminary design yourself, then take it to your aerodynamicist to improve. That will save time and money and you will learn lots. Then Id look into construction methods, think you can undertake it alone? Yes? Great go for it. No? Then hire a couple hands to help but you can be there to cut metal or clean tools etc. The more time your there cleaning and helping set up {even helping work?} the less time your paid hands are required. I would only employ them for the times I NEED them, finish work can be done alone {smoothing work, primeing, etc}. Then youve got a plane that you {your now a pilot!! lol} can go test fly and improve on until the air races! Either way Id suggest at least making a hobby wind tunnel, there are plans on the net and if your interested in it its a lot of fun! Sorry if I stepped on any toes, just saying what I would do.

I will continue to check in on this thread but you can always reach me at steveyb4342@hotmail.com {that goes for anyone on this board}.

Thanks Steve

Stevey
04-12-2007, 03:16 PM
By the way I would not tilt a V8 90 degrees unless it had a very efficient dry sump oiling system. The engine would be more likly to starve of oil if slanted at 90 degrees and the engine would have reduced amounts of hp due to the crank shaft having to hit the oil and push through it, it's better if the crank shaft never touches the oil in the oil pan. Thats why the old drag racers known as "gassers" used to purposely run a quart or two low of oil. Thats also why windage trays are now installed in race cars. Dry sump oiling systems prevent race cars from starving of oil when they corner hard and it also eliminates the oil sloshing around in the oil pan, there are more advantages but they are soley for auto racing. Hope this helps!

Steve :beerchug:

LoveOldPlanes
04-13-2007, 01:17 AM
Just Thoughts:

Why try and modify anything automotive and watercooled? Anybody remember there will be a complete cooling system to add to the aircraft in addition to engine weight? To cap all, think of all the machining expense....that's going to rack up the cost too.

How about this: Base your engine on as many existing aircraft engines parts as possible to keep cost down, and to make the engine affordable to actualy run and repair. Use cylinders from a Lycoming or Contiental, but instead of an opposed engine, build a radial center section to mount everything on. You'ed have readliy available cylinders, pistons and rods, pushrods, rocker arms, valave springs and keepers....you get the idea. Machine your master rod assembly to mate to existing rods. Stack up as many cylinders as you can cool and use existing gear reduction parts also. Everyone knows you can get better overlap from a round engine, so you are ahead of the game there also. You need more power, add a row. You could run a nice pressure carb that already exists to juice it all. Build your own baffles and cowling to match, add in a nice turbo-compounding system to regain some lost heat energy.

How's that sound?
Randolph

First time Juke
04-13-2007, 03:45 AM
I do know that some hemi's in funny car's CAN make up to 2600hp, but I cant imagine they are the most reliable engines in the world.

I think this sounds like we might have ourselves a converstion with different views.

I know very little about aviation engine making, but I have about 15 model engines of various types.

BEDEs used to have japanese aluminum car engines and those flew fast.

Hemis are more rugged in construction I assume ?





Here an insert from the link I passed on the previous page;




[edit] LSX
At the 2006 SEMA show, GM Performance Parts introduced the LSX engine, an all-new cast-iron racing block based on the LS7 engine. It was designed with help from drag racing legend Warren Johnson, and despite being based on GM's small-block design, it offers displacements ranging from 364 cubic inches to 511 cubic inches (4.25" Bore x 4.5" Stroke) and is capable of withstanding 2500 bhp. This block incorporates two extra rows of head-bolt holes per bank for increased clamping capacity. The six bolt steel main caps are the same ones used on the LS7 engine. The engine debuted at the auto show in a customized 1969 Camaro owned by Reggie Jackson. The LSX will be available starting the second quarter of 2007, set to be available in authorized dealerships and retailers on March 31, 2007.[2]

First time Juke
04-13-2007, 04:17 AM
Sorry if I stepped on any toes, just saying what I would do.


Really no need to apologize. Give me time to think and react. :thumbsup:

Stevey
04-13-2007, 09:55 AM
I agree that to some using an automotive engine may be the wrong way to go. BUT I believe it is much more cost effective, easier to get parts for and possibly create more power using an automotive engine. Machineing does not actually cost that much in comparison to some of the other bills included in attempting to design and build a air racer.

Juke, You are right the LSX block from Chevy is going to be the ultimate block. As a matter of fact Im going to be buying one for my camaro. Yes the LSX can easily withstand up to 2500hp and more {2500 is only a factory recommended stop point :D }. The only problem is that block has not been realeased as of yet {a few more months I believe} and we have no idea what kind of "growing pains" that block may occur. We wont know if that block is known to crack until we get a few top fuel chevy dragsters or funny cars out there pushing 2500-3000hp with that block. But I do agree it will make one wild engine when done up right!! I recommended a hemi because they are a proven design thats been around since the 60's {I believe maybe more or less} and since then most all of your high power monsters you see are running hemi's, so we know its a strong platform to build from. The hemi holds a reputation, the LSX has a reputation to START. Your right hemi's do have a very rugged construction but who knows what the LSX may bring???

Cooling a car engine can be done quiet easily and need not have "heavy cooling systems", you just need to be creative. As a matter of fact I believe 30% of an aircraft's drag is due to cooling systems and ducts in the cowling, for my engine in my sport class design I have designed a system that shouldnt much in the way of drag inducing cooling ducts if any at all. You just gotta think outside box. :D .

So are you looking into fuel injection or carbureted? What kind of fuel will you run? I assume all planes must run whatever is on the field? What octane would that be? Also still interested in the weight and hp/kg ratio your looking into. Id like to know as much about your project as your willing to tell. Even if its just for me to think about, if you want my feedback Id be glad to give it.

hahaha take all the time you need my friend!

Steve :beerchug:

AirDOGGe
04-13-2007, 06:34 PM
Something you have to remember about drag racing engines.....They only have to produce those high power levels for a few seconds.

Likewise with hot rod engines. You might get 1000 hp out of that big block Ford for a quick run down the boulevard, but try keeping it running at redline for a 20-minute drive. Odds are, something is going to break.

You simply cannot compare car horsepower with aircraft horsepower, since aircraft engines work in a completely different environment and suffer from more severe vibrations.

.

Stevey
04-13-2007, 06:59 PM
I agree with what you said. That would be why you would obviously have to tailor the engine to such an application. Also if you use the proper parts with the proper part it shouldnt have a problem sustaining high RPM's. Also if you properly tailor the engine to your appliation you can use a cam that would make peak hp at lower RPM levels. Even if you cant get it low enough if you keep the engine cool and it was properly built it should have no problems sustaining the RPM, you may have to sacrifice some hp by using a slightly heavier rotating assembly so they can withstand the pressures but it wont be any big amount an you may get around that if you attempt to build and test with new alloys. I mean thats what it's all about isnt it? Testing theories and seeing which ones faster and what you can do tomake something work better {faster}. As for vibrations, this can also lead back to properly tailoring the engine to what you want to do and on top of that the gear reduction box should be able to reduce a half decent amount of the vibration felt by the engine. I think it's a very possible plan to use an automotive engine to take a plane to great speeds its just that it make take some time and design considerations but then again what doesnt?

Steve :beerchug:

Stevey
04-16-2007, 01:28 PM
Wow Juke you must be thinking hard! :D . I hope your plans are working out like you had planned! :thumbsup:

Steve

First time Juke
05-16-2007, 02:04 AM
Wow Juke you must be thinking hard! :D . I hope your plans are working out like you had planned! :thumbsup:

Steve

Steve,

My time goes ( besides work ) 100 % to the new born baby and making garden around our new house.

I have seriously tought of giving up any further planning of any new racer in near future at least. I had few years back a serious disc problem in my spine and I think it was not treated 100 % correctly. Even if I was 100 % healthy this would be tramendous task to set a new record.

One thing I realized after having designed TS II that it was still longer than Rare Bear..newest design is more closer to Rare Bear dimension...but think about it..Tsunami, MA II, Pond Racer all failed...and those were professionals who built and designed them..would I seriously have any change even if I had the dough to do it ?

I don't think a single car engine is able to make it.


best regards,

( a former thrillseeker and today a dedicated daddy )

Juke


PS: I still try make the TS II model fly this summer with a new engine.

AAFO_WSagar
05-16-2007, 08:36 AM
Heck with all that Jukka.. pix of the new member to yer family and the mommie too!

:thumbsup:

First time Juke
05-17-2007, 09:57 PM
Heck with all that Jukka.. pix of the new member to yer family and the mommie too!

:thumbsup:

Here is the little princess !

I added also the pic that is behind.

First time Juke
05-17-2007, 10:33 PM
...and the mom...doctor of medicine..Kirsi-Maria !

Proud Mary ( dressed up for a costume party ) !

AAFO_WSagar
05-18-2007, 02:52 AM
LOL!! Cute kid!! Mom's gonna kill ya when she sees ya put that photo on the net ya'know... :eek13:

First time Juke
05-18-2007, 03:16 AM
Thanks,

Highly unlikely she's gonna surf here. Her cousin just turned a professional hockey player and appeared on the World Champ's final a week ago.
Cuter pics are at home unfortunately. She is a red head. Hair visible in our dining room below.

rgds,

Juke

First time Juke
05-18-2007, 07:09 AM
Hey Steve !

I just figured that TS II is roughly 3 feet longer than a Thunder Mustang and 5 feet shorter than a P-51D Mustang. About 2 feet shorter than a Rare Bear. ( 6 feet more span than in a Thunder Mustang ).

Wonder if that is unstable at flight ?

...and don't forget...R&R is a car too...so thence a Merlin is a car engine as well !! :)

best regards,

Juke :bullhorn:

Stevey
05-22-2007, 12:08 PM
Hey sorry I was so late getting back to you, Im in the middle of building a couple engines. I think you can do it Juke. Do you have any plans you can post on here? Id love to see em! Anyways I gotta get back to work Im on a deadline. Ive got some big plans coming! For cars and planes lol.

Steve

First time Juke
06-07-2007, 07:34 AM
Do you have any plans you can post on here? Id love to see em!

This is really where my expertise ends...I was thinking a wooden plane with certain metal parts like in a Mossie. Not that I would not understand about details..I just have no experience building a real airplane. If one intends to make a lite metal kite of this then P-51 H is the source for fine details.

The " thing " if you will in my TS II was / is that wing has been swept and moved forward...gear folds in the wing and does not come to fuselage area...partially fuel tanks are also in the wings. Flying tail and naca scoops and some packing for all major parts to save space. This was the main goal...to make it sleek and small, but not too small.

Anyone who feels this could be ok...can go forward from here. This whole kite is 50% a team effort with folks in Pylon 1 and AAFO.com

rgds,

Juke

Stevey
06-07-2007, 06:35 PM
I cant see wood being a very stable structure. I realise some lower performance/older planes were built with wood and cloth. The thing is you were talking about 2500 hp at one point, wood will not be able to hold that kind of hp. You would have to make it VERY strong and VERY heavy. I cannot see that being a very good option. Have you made sketches of you plane? Could you scan them? I dont understand quite what your saying and Id like to see it {Im a visual learner}.

Steve

First time Juke
06-08-2007, 04:39 AM
Have you made sketches of you plane? Could you scan them? I dont understand quite what your saying and Id like to see it {Im a visual learner}.

Stevey,

There are even jets made outa wood like Vampire.

Here is the TS II like it has been for two years now;

http://img436.imageshack.us/img436/262/tigersharkii20053og.jpg

First time Juke
06-08-2007, 05:02 AM
To be 100% honest...one little change has taken place...flightposture is more upright ( tail high ) and prop thrust vector thus changed a bit..like in the enclosed pic.

Wing structure has been the main concern so far...the FW 190 D-9 wing is pretty good to start with structure wise.

The model wing is a very rugged wood piece. Wing tanks would have to be in between main spar and trailing edge spar ( possibly forming a hollow shell structure ).

Stevey
06-09-2007, 05:50 PM
That looks pretty cool Juke, it kinda reminds me of a P-51. Can you tell me where you founf those power to weight ratios you posted a while back in this thread? Do you have any more info like that?

Steve

First time Juke
06-11-2007, 03:00 AM
Can you tell me where you found those power to weight ratios you posted a while back in this thread? Do you have any more info like that?

Steve

I have been figuring them out...this TS II would be 1,27 hp/kg..definitely in par with Rare Bear. I am not sure of Rare Bear power to weight ratio but I take an educated guess and it is very close if not above 1,0 hp/kg.

I search the sites ( Heinkel H-100 D ) and just calculated them when known power and weight are given.

There is a peculiar thing...It seems that a bigger plane with same power ratio seem to be faster..I think the pilot + avionics compo wight cannot be changed and thus more power gives more reserve power to lessen the pilot weight.

See Pogo...huge props and small and nearly 5850 ! Estimated top speed 610 mph.

http://www.nasm.si.edu/research/aero/aircraft/convair_pogo.htm

Power to weight ratio 1,0 hp/kg.

First time Juke
06-11-2007, 06:14 AM
That looks pretty cool Juke, it kinda reminds me of a P-51.

It also reminds a bit of the straight winged Dewoitine 520 fighter.
This is considerably "packed" version of a Mustang. Pretty much like Tsunami concept..less frontal area and less wetted area..the need to escort bombers is no longer there this has no guns nor ammo and holds less fuel.

Stevey
06-11-2007, 01:52 PM
Wow my purposed plane has quite the power to weight ratio. Combine that with some half decent aerodynamics and a strong structure and she should be pretty fast! :D.

Steve

First time Juke
06-12-2007, 04:38 AM
Wow my purposed plane has quite the power to weight ratio. Combine that with some half decent aerodynamics and a strong structure and she should be pretty fast! :D.

Steve

Stevey,

Let's see your intented racer 3-views !

Finnish AF had a plan in 1943 to make small wooden fighter armed with just 20 mm cannon to tackle with new the enemy fighters. It was to use the same DB engines as the Me 109 G-2's already had in the squadrons. This Puuska PM-3 fighter was really small and in 1943 planned to go 450 mph. I recall it was supposed to be just 7,8 meters in span. The arrival of the Me 109 G-6s ( + 10s ) made all these plans futile. After the war a one wooden PM-1 was made; it was bigger than Me 109 G and slower.

I think a small plane wit lotsa HP:s could be the answer if carefully planned.


rgds,

Juke


BTW: Here is the data of the last Heinkel piston "racer" P1076.

http://www.luft46.com/heinkel/hep1076.html

Insert from the story: Although this project did not see the light of day (although Siegfried Günter completed detailed drawings and plans for the Americans in mid-1945), it probably would have been one of the fastest piston-engined propeller aircraft ever built.

Last FW was supposed to have 0,6 hp/kg power to weight ratio and go 725 kmh.
http://www.luft46.com/fw/fwbmw802.html

Stevey
06-12-2007, 05:22 PM
Unfortunatly Juke I do not have a scanner, and I only have very bad drawings. I am currently working on having some better plans drawn out. See I have it in my head and I know all the dimensions etc but I'm a terrible artist and am computer illeterate. So I have my girlfriend helping me do some 1/4 scale plans. Not that I need them but if/when I start to produce a kit I will need something to go by/send as instructions.

To try and picture it think of a small P-51 fuselage without the cooling duct on the bottom and the exhaust. Then add the wings and epennage of a NXT. That should give you the basic idea. Theres some more changing to it etc but thats the basic look. Itll be all carbon fiber "skins" with tube frame inside and maybe some reinforced structural "foam" for more support in spots that are needed.

That heinkel looks pretty neat!

Steve

First time Juke
06-13-2007, 02:19 AM
Yes Ernst Heinkel solved the heavy engine installation induced CG problem like Burt Rutan in the Pond Racer by making a forward swept wings.

Stevey
06-13-2007, 05:34 PM
Yea that would be a problem luckily my engine is going to be pretty small compared to some others.

Steve

First time Juke
06-21-2007, 01:43 AM
To try and picture it think of a small P-51 fuselage without the cooling duct on the bottom and the exhaust. Then add the wings and epennage of a NXT. That should give you the basic idea.

That heinkel looks pretty neat!


Here is a better pic of the FW 802

http://www.luft46.com/vaart/gg802-1.jpg

Pretty bad or what ? :rolleyes:


Very fashionable to make a plane wings look like NXT; all small electro R/C racers look a bit like it.

Is it a metal plane or a fiber/carbon structure ? Could metal kite be made to look like NXT in a small racer ? :dunno:

Stevey
06-21-2007, 06:33 PM
Man that thing looks MEAN! Yea It wont be exactly like a NXT but it will be sorta the same look. Do you mean my plane? Itll be carbon/kevlar composite with a metal tube frame inside.

Steve

First time Juke
11-22-2009, 02:52 AM
I just found out that Hemi 426 based Top Fuels can produce 8 000 hps. How the heck is that possible ? It weighs only around 200 lbs.

Race5
11-22-2009, 09:43 AM
I just found out that Hemi 426 based Top Fuels can produce 8 000 hps. How the heck is that possible ? It weighs only around 200 lbs.

The power comes from the fuel. They run 95% Nitromethane at flow rates of several hundred gallons a minute at full throttle. It could NEVER be used in an aircraft as the lifespan of one of those engines is measured in seconds.

AirDOGGe
12-05-2009, 03:42 PM
The power also comes from massive pressurization, via supercharger(s) and/or turbocharging. The top fuelers run HUGE levels of boost, up to 50 PSI. The more air AND fuel you can cram into the cylinders, the more power you can make.

The fuel pump puts out about 400 pounds per square inch just to be able to inject it into the cyinders quickly enough.

They also use a lot of nitrous-oxide boost, to increase the amount of oxygen in the fuel/air mixture.

The fastest cars burn 4 to 5 GALLONS of fuel just during that 4+ second 1/4-mile run, so there's no way an aircraft would be able to carry enough fuel for a full race anyway!

It's amazing to think that just ONE CYLINDER of a top fuel funnycar's V8 produces something like 750 horsepower all by itself...Rare Bear's 4000hp 18 cylinder engine makes about 220 hp at best ber cyl.

First time Juke
12-11-2009, 02:26 PM
How about an air cooled v-8 like here the TATRA made in Checkoslovakia.

http://en.wikipedia.org/wiki/V8_engine

AirDOGGe
12-12-2009, 03:01 PM
Why not? They already have opposed-8 cylinder air-cooled engines in aircraft, like the Lycoming IO-720.

http://www.lycoming.com/engines/series/720-series-engines.html

First time Juke
12-13-2009, 02:23 AM
Why not? They already have opposed-8 cylinder air-cooled engines in aircraft, like the Lycoming IO-720.

http://www.lycoming.com/engines/series/720-series-engines.html

Cool...really cool. I wonder if that could be enhanced to go safely at 800-1000 hp ?

In a racer that engine could mean this ?

Dart was supposed to be some 12 ft longer and 3000 hp stronger.
http://aero-comlab.stanford.edu/Papers/AIAA-2000-4341-839.pdf

AirDOGGe
12-13-2009, 10:37 PM
Cool...really cool. I wonder if that could be enhanced to go safely at 800-1000 hp ?

In a racer that engine could mean this ?

Dart was supposed to be some 12 ft longer and 3000 hp stronger.
http://aero-comlab.stanford.edu/Papers/AIAA-2000-4341-839.pdf

Don't forget weight in your specs. That big Lyc weighs 600 lbs alone!

First time Juke
12-13-2009, 11:29 PM
Don't forget weight in your specs. That big Lyc weighs 600 lbs alone!

I know AD.

I have 1530 lbs to go...in a plane that is only 17 ft long.

But you might be right..if I use 800 hp the increased speed do need really strong structure or/and really genius one.

AirDOGGe
12-18-2009, 01:29 AM
Here's an engine that may interest you. $200,000 per engine though.


http://www.traceengines.com/



the Trace V-8 engine represents an evolution in engine selection.

The turbocharged, liquid-cooled engine improves operational performance by increasing speed, range, and gross weight without increasing operational cost; TRACE Engines estimates that with the combined lower cost to purchase, repair, and overhaul, operators can save 35% to 50%.

As Czarnecki explains, while a turbine engine displays constant power degradation as altitude increases, the turbocharged TRACE V-8 maintains cruise power all the way up with an estimated 600hp maximum takeoff and 500hp maximum continuous; an equivalent turbo prop engine would need to be rated as much as 1,000 horsepower at sea level to match the TRACE engine’s output at altitude. The result is an average 27 gallons per hour fuel rate, less than 30% than the fuel rate of an equivalent powered turbine engine.

Currently, typical installations can be found in singles with gross weights up to 6,000 lbs and twins up to 12,500 lbs. The starting price remains at $200,000 for an engine package, with total installation costs varying due to time and labor. TRACE Engines LP is located in Midland, Texas where its production facilities are able to produce around 100 engines a year for over 40,000 potential aircraft retrofit opportunities.


:cool:

First time Juke
12-18-2009, 02:04 AM
Here's an engine that may interest you. $200,000 per engine though.

http://www.traceengines.com/

:cool:

Really cool lookin engine but since it need a radiator it is too large system for my small design. Air cooled IO-720 sounds good for racing. How pricy are they ?


http://en.wikipedia.org/wiki/Lycoming_IO-720

Looks like 70 000 usd for used one.

AirDOGGe
12-26-2009, 10:08 AM
Looks like Kevin's (gonna use, or is using, or WAS going to use) one of those Trace V8s in his next racer:




TRACE Engines LP to Power Kevin Eldredge's new Nemesis NXT


Kevin Eldredge, SuperSport competitor in the Reno Air Races and one of the fastest men in airborne motorsports, announced today that he has accepted the sponsorship of TRACE Engines, LP., of Midland, Texas. The TRACE V-8 will power a new Nemesis NXT that Kevin will build with Andy Chiavetta of Aerochia, who has built Sport champions and provides go-fast carbon graphite components for Lancairs.


"I am absolutely thrilled that I will be the first to use the TRACE V-8 power in a race plane, and my next Nemesis NXT will show the community what good American V-8 power can do in a modern airframe," said Eldredge, to a group of reporters at the Reno Air Races.


"We are excited to sponsor Kevin and the new TRACE Engine Racer. His background, experience, knowledge, and his competitive spirit are perfect for this sponsorship/partnership. We look forward to working with Kevin over the next year, until we see the machine publicly at Reno and airshows next year," said TRACE COO David Czarnecki.


TRACE Engines LP manufacturers the FAA Certificated, 600 horsepower, 495 cubic inch, turbocharged V-8. The powerplant for the TRACE Engine Racer will be modified to produce additional horsepower and be packaged specifically for installation in the NXT.


Note that this article is dated September 14, 2008. Is Kevin flying behind a Trace now, or building a plane for one? No mention of it on his website. Maybe the deal fell through?


P.S.....If he can make one work in an NXT, Juke, then it should work in yours. The airframes are of similar size. If you want to race it eventually, you'll need that extra 200 ponies for Super-sport class.


:thumbsup:

First time Juke
12-28-2009, 01:59 AM
Looks like Kevin's (gonna use, or is using, or WAS going to use) one of those Trace V8s in his next racer:


Note that this article is dated September 14, 2008. Is Kevin flying behind a Trace now, or building a plane for one? No mention of it on his website. Maybe the deal fell through?

P.S.....If he can make one work in an NXT, Juke, then it should work in yours. The airframes are of similar size. If you want to race it eventually, you'll need that extra 200 ponies for Super-sport class.

:thumbsup:

For what I can see the tractor vs. pusher of this kind examples I am inclined to predict that a really small pusher with mid engine needs ½ the hp to reach same speeds than a tractor.

There is a one exception to this rule...it seems to be Jon Sharp and his entire NEMESIS lineage. They all seem to "bang on through with ludicrous" speeds albeit being tractor lay-out planes.

Planes that I refer to are Sierra Sue S-1, Lear Fan 2100 and Gallaudet Bullet Pusher and Lars Giertz VMaxProbe.

So I may not need a 100 000 dollar engine to go 400 mph. I possibly can do it with ( or someone else can ) 50 - 60 000 usd engine.

I have had a change to get a new job so the changes to actually build something have become better by 200%..:)

Happy New Year 2010 folks !

First time Juke
12-28-2009, 07:30 AM
So I may not need a 100 000 dollar engine to go 400 mph. I possibly can do it with ( or someone else can ) 50 - 60 000 usd engine.


Make it 14 500 usd engine ( 10 300 € )...:)

http://www.homebuiltairplanes.com/forums/sale/2235-jabiru-5100-sale.html

Race5
12-28-2009, 09:14 PM
Since top fuel engines were mentioned earlier, I wanted to throw this up. This video shows the amount of fuel used in ONE of 8 cylinders during a top fuel pass.

http://www.youtube.com/watch?v=T5lrMWszCR4

jimmyboyB50
01-01-2010, 09:09 AM
Hi All,
I am an aviation engine guy and have built F1 engines in the past. Please remember to KISS keep it simple s....

My thoughts have always been on the TIO/TIGO 541 series.
TIO-541 has the cam on the bottom and a very complicated accessory section and is direct drive. The benefits are higher reving 2900RPM and a very interesting oil cooled exhaust valve guide. As with most Lycoming very nice intake design. I believe its 325 HP that said with a bump up of the RPM, MP, ADI, air cooling spray, auto style fuel injection, electronic injection, and knock sensor. I would also look at the TIGO rods to see if they are stronger and a difficult task of machining the accessory case off and go electric for the accessories. You could push ~500HP. This engine is on the Beech Duke

The TIGO is geared and produces 400HP other than that they are similar. This engine is on the Piper P Navajo

A couple of years ago at Reno I asked the designer at the Lycoming tent about the idea and he agreed the 541 had more capability but said they would not build a race engine on a model that they did not plan to sell.
Good luck

FlyKidChris
01-27-2010, 08:52 AM
JimmyBoyB50,
I've wondered about the TIO-541 or GTIO-541 in a sport racing application, too.
IIRC, the TIO-541 in the Beech Duke (or Baron 56TC) was rated at 380 hp and the geared version in the pressurized Navajo was rated at 425 hp. According to Wikipedia, the highest "stock" rating was 450 hp (geared, turbo-ed and intercooled). That seems like a good starting point, to me.
I wouldn't normally call that 450 hp version simple, though.
Chris

IcePaq
06-12-2010, 07:51 AM
I'm amazed that modern engine management systems are not the standard on these planes.

We're getting near 1800hp out of a street driven car that blows pretty darn clean on the gas analyzer without a hint of detonation.

Even nitrous systems are going "closed loop".

First time Juke
11-08-2010, 08:14 AM
2-stroke engines:

I figured if you make really small plane like Cri Cri ( french classic twin...world smallest ) there seems to be still room for a 2-stroke ( and also electrics are gaining ground ).

I have so far found out that a Sachs Dolmar based small 2-strokes may be very efficient.

One maker claims his APT 6.4 cu in engine has only 0.3 OZ / min consumption @ 65 % power. Engine produces 13 hp...thus 8.4 hp would be 65%.

Some experts say this is simply impossible. Maker says his reed valve and 100:1 oil ( Amsoil ) makes the difference.

Is this plausible ? If not what is ?

Does nicasil in the cylinders ( or any other coating ) have a big effect ?

GeoffS
11-08-2010, 10:23 AM
Is that Oz weight or Oz volume?

First time Juke
11-08-2010, 11:27 PM
I have no idea...I have always figured one oz is 28 grams.

Air Power Technologies could advice more.

Blue Foam
11-16-2010, 04:19 PM
2-stroke engines:
I have so far found out that a Sachs Dolmar based small 2-strokes may be very efficient.

One maker claims his APT 6.4 cu in engine has only 0.3 OZ / min consumption @ 65 % power. Engine produces 13 hp...thus 8.4 hp would be 65%.
....
Does nicasil in the cylinders ( or any other coating ) have a big effect ?
Coatings do make a difference, not in this case. The numbers listed work out to .80 lb/HP/hr, about half way between a Continental at cruise (.38) and an unlimited on ADI (1.3). .80 is efficient for a small-bore 2-stroke, i.e. not very efficient. This number is not efficient for a long range aircraft, it might be quite suitable for a shorter duration UAV where engine weight is as significant as mission fuel weight.

First time Juke
11-18-2010, 02:30 AM
Coatings do make a difference, not in this case. The numbers listed work out to .80 lb/HP/hr, about half way between a Continental at cruise (.38) and an unlimited on ADI (1.3). .80 is efficient for a small-bore 2-stroke, i.e. not very efficient. This number is not efficient for a long range aircraft, it might be quite suitable for a shorter duration UAV where engine weight is as significant as mission fuel weight.

Your reasoning sounds solid. But I may remind you here the maker claims his engine consumes only 0.06 liter/HP/hr ie. 0.1 lb/hp/hr. But as you mention if he claims it is per one HP not the engine consumption in general..then you are correct !

If so then I do have found a better engine that burns only 0.36 l/hp/hr at 90% powersetting.

Here is the APT figure I mean; http://airpowertechnologies.net/UAV_64cuin.html

Well even if is per 1 hp then it isn't better or worse then others ..just normal I guess.

How come I did not notice it could be just one hp they meant ?

Maybe because others publish the total consumption like here for the DA-85; http://www.desertaircraft.com/engines_detail.php?Page=DA-85

IcePaq
11-24-2010, 02:26 PM
We're now getting near 2400hp from our 5.4 liter twin turbo ford GT which is a street driven car.

At lower boost levels, this car runs pump gas and is pretty sedate because it really doesn't have to run as radical of a cam with the 4 valve heads.

Still.......the frontal area of a merlin is actually smaller than this ford modular engine.

First time Juke
11-30-2010, 03:56 AM
Install it mid fuse like this was in P-75; http://en.wikipedia.org/wiki/Allison_V-3420

First time Juke
12-29-2010, 07:13 AM
ZDZ has 420 ccm 2 stroke;

http://www.troybuiltmodels.com/items/ZDZ420B4.html

Wonder if that could be ( if doubled ) to move this enclosed bird at 350 mph ?

Originally that is 35 hp but tweaked maybe 2 x 50 hp ? That does not sound much but in that bird it is more power to weight ratio than a stock Mustang P-51D has.

Could that be eligible to race in the sports class ?

Plane would be smaller than Cri Cri or BEDE 5B.

The nacelles would be bigger naturally as what drawn here.

Race5
12-29-2010, 07:19 AM
ZDZ has 400 ccm 2 stroke;



Could that be eligible to race in the sports class ?




I hope not. That is way too small to be running in the wake of a 420 mph NXT.

First time Juke
12-29-2010, 07:29 AM
I hope not. That is way too small to be running in the wake of a 420 mph NXT.

Hhahhahah !

Good one...since NXT cannot compete in unlimited class this Fenix cannot compete in Sports class.

What if I tweak it to go 430 mph and keep the NXT in wake turbulence ?

It would need two 25x38 props at 8000-8500 rpm to go beyond 500 mph.

I have not calculated if that makes the props go beyond speed of sound..possibly but then more blades and smaller dia ( like 24x38 ).

-----------

The prop would stay at 607 mph ( 970 km/h ) under the speed of sound at any rate.

Race5
12-29-2010, 08:12 AM
Hhahhahah !



What if I tweak it to go 430 mph and keep the NXT in wake turbulence ?



You'd wake up. No dream ever ends the way you want it to.

First time Juke
12-30-2010, 01:59 AM
You'd wake up. No dream ever ends the way you want it to.

This is true..none of my aviation dreams at least.

:beerchug:

The ZDZ 420 version added below: