Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by KC135DELTA, Jan 29, 2010.
Care to post pictures and provide specifics?
I think it's this one RPi Engineering - V8 Engines
No, sometimes I learn stuff if I slog through it. See, I'm well read too.
You forgot to correct me on where you live.
Join Date: Jul 2009 Location: Leiden, Netherlands Posts: 1,499
That's why you need a bigger diameter prop in front than in back and a psru to run it.
Also, having a big prop in front and lower doesn't gain you much in the gear leg shortening department either.
enclosed photos PSRU & Land Rover engine
Looking at your first picture, is that a drive-shaft in the middle in navy blue color?, seems like it's a steel car type drive-shaft, what type of coupling do you use, do you have a picture of it?
http://tagazous.free.fr and search E-Racer
[FONT="]Canard E-Racer with V8 autoengine 4,6 liters injection
Total retractable gear.
This aeroplane is alone actually in France with V8.
Two seats, central engine cooling by water, transmission, gear box, pushing propeller.
Main frame in resin and fiberglass as Varieze/Longeze/Cosy. Carbon fiber in canard and gear legs.
Engine is V-8 electronic injection 4,6 liters from Land Rover 165kw (225 HP on car).
Parameters are :
Span 7,98 m
Lenght 5,11 m
aera 10,15 m2
Max speed (Vne) 480 km/h (260kt)
Cruise speed à 75% 300 km/h (162kt)
Maxi load 930 kg
Stall speed (parachutage) 110 km/h(59kt) at 820 kg - 115 km/h(62kt) at 930 kg
Croos wind landing tested 20 kt (37 km/h)
Take off at 930 kg 580 meters
Landing lenght at 930 kg 590 meters
Flight duration 6h30mn plus 1/2h saffety time
avgas 100LL per one hour from 20 to 26 liters for cruise speed from 280 à 320 km/h
using avgas 100LL
possible to use 100LL or no lead 98
ascentional rate 1500 à 2500 ft/mn
best ascentional speed 105 kt
best lenght tested at 880 kg : 17 : with 100kt speed
Down wind speed 100/105kt
speed to put out gear legs 120 kt
Final speed 80kt
Landing speed 70kt
Speed take off from 70 to 80 kt and 100 à 110kt, gear off 500ft, ascentional at 100 to 110 kt, cruise super chip at 140kt(260km/h)(19l/h), chip cruise to 150kt(278km/h)(21l/h), cruise 75% 162kt(300km/h)(26l/h), high speed cruise 180kt(333km/h)(26l/h), maxi speed tested 216kt (400 km/h).
Maxi load pilot+passager 180kg (front balance)
Note: An other E-Racer is near ready to fly in France with also PSRU and auto-engine V6 (180 HP)[/FONT]
engine-> connexion with driveshaft -> spline connexion to PSRU with rubber absorbor (flector)
btw how many hours have you logged with that setup?
Thank you - that's a first. I don't think I've seen a remote mounting of this sort before. Looks very interesting. Does the gear box lubrication work with the engine's?
...and what is the reduction ratio (engine cruise RPM)?
Also, what does the all up powerplant weigh (engine, drive, fluids, etc)
I have fly only 60 to 70 hours with this configuration (and test on ground around 10 hours at several rpm to check vibration level).
i have bought thes drive tree / PSRU from shirl Dickey for e-racer but before using i have check and open the psru and done some small modifications: calculation of all gaps and grind metal steel ring to adjust exactly the position inside psru of all elements.
rebuilt the nose flector (inside the rubber flector).
gear box lubrification is with oil W100 (around 1/3 of the inside box).
gear box come from "CASALE" (www.casalev-drive.com).
gear reduction is 1.56 to 1 for the V8 (225 to 240 HP)
and 2 to 1 for V6 (180HP)
So this pretty much the stock e-racer setup, overall, is it not?
gear box come from "CASALE" (www.casalev-drive.com).
gear reduction is 1.56 to 1 for my Land Rover V8 (225 to 240 HP)
and propeller is 1,66 meter diameter and 2,30 meter pitch
injection map is changed to have the maximum torque between 3000 to 3500 rpm at engine
economic rpm for engine and good speed
maximum rpm for this engine is 4500 to 4750 rpm
plane weigh with all oil/water ...instruments ...etc complete is 635 kg (maximum 930 kg)
Weight of reductor included intake spline, réductor supports, flector and propeller support is 34 kg
Weight of engine land rover 4.6 liters injection with oil inside and supports, and computer engine is 183 kg
Weight of water radiator with water/glycol and tubes and ventilator is 18 kg
note that rubber of flector is not in place on photo of psru
This is actually something I don't think we've touched upon here previously - using a marine drive as a reduction for an automotive based installation. An acquaintance of mine about twenty years ago built up a Mazda 13B with a marine box (ZF or Hurth, don't recall exactly which). Although a bit heavier than optimum, once the extraneous pieces were removed from the box (clutch, reverse gearing, shift system, etc.) the install was pretty simple (his application was a BD-4) and not too punishing weight wise.
In his case he modified a Mazda bell housing to fit the marine drive but as seen here, there is no reason the drive could not be remote mounted with its own support structure and prop shaft extension.
The marine boxes are made to relatively high quality standards (many use AGMA 12 gears, or better in a few instances) and have duty cycle ratings very similar to those we see in airplanes. For a quick and durable option, this is a viable approach and certainly seems to work for the E-Racer application.
Orion you said a couple times about if I remember correctly air-boat PSRU, you gave even a link, but can't find it now. It might make sense, there is bigger market for boat PSRU, they often also use cars engines, and it seems that boat guys have more experience with them (they deal with them for years), but I worry about two things, flight loads and potential problems with PSRU cases, and weight (but those things might exclude each other), in planes, people care about every pound in boats not necessary, those PSRU are probably over-engineered. But if those Vulkan coupling (marine coupling) might work in airplanes, you wrote about them in other pusher thread, maybe marine PSRU might work too with success. Do you know weight of Powersport, or Geschwender PSRU just for comparison?
The Powersport reduction is much lighter than the Geschwender unit simply because of the differences in application. The V-8 based unit is about 80 pounds if I recall right, whereas the Powersort unit is about half that.
As far as the duty cycle for the airboat redrives is concerned, I think they actually see tougher service than a typical airplane application would. Here's a new one I found recently (http://www.airboatgeardrives.com/index.html). The other one I liked was called Rotator (http://www.classicairboats.com/ROTATOR-REDUCTION-1726.Category.html).
More reading on topic http://www.engdyn.com/images/uploads/97-prevention_of_torsional_vibration_problems.pdf
Just learned two new words in English "strain gauge" we were using this stuff a couple times during laboratories, now I know how to call it Eng .
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