Is it a reducer between the engine block and the hub? How is torsional vibration handled? Especially in half-engine mode... Any idea of the TBO?

The RED Maintenance manual states a 1000 hour TBO. I know that it is certainly RED's intention to expand this based upon operational experience. Though it's still very early days for the engine, I can say that for the 40+ hours I flew it in a stretch, it was not necessary to add any oil at all! The engine does have and "avoid" RPM range for vibration, but it is not in the flight range, but rather the ground idle range. It was equally smooth in half engine mode, as it's a "straight six" developing power from one half, and the other half is still compressing, though not developing power.

Wouldn't a mechanical failure on one bank that did not allow rotation or required more than normal torque be an issue with running the other bank?

Sure, anything mechanical can fail. A severe mechanical failure can result in an engine failure. The redundancy of the two independent banks is more to insulate from a full engine failure as a result of an injection pump, injector bank, electrical, FADEC, or coolant failure on one side.

OHI ("One Half Inoperative" and Fuel Pumps, Range, Endurance? Time Limit?
 

A highly interesting development!
Is the I/O Fuel Pump still pumping fuel around, or shut/off from fuel and mechanically decoupled?
- If range or endurance maximisation were desired, would shutting down one half help extend range/endurance by running the other half at a more efficient power setting at lower airspeed, or is the still compressing Dead Half taking away too much power from the Live Half to leave an advantage?
- And is there a time limitation for flying with a Dead Half? Is OHI for emergency only, or an operational option, are shut-downs/restarts allowed for pilot training?
Thanks for any further insights (just curious)

jr

Since the diesel is a compression ignition engine, no electricity is required to run it, assuming it has a mechanical fuel pump which I am sure it does. No spark plugs, no magneto, etc. A six cylinder inline engine can be fully balanced, so running on a single bank shouldn't have vibration issues. Interesting project, well done!

In the purest form of a diesel engine, yes. In the case of the RED A-03 engine, electricity is required to run it, as it is FADEC controlled. The engine power is controlled by electrically operated fuel injectors, and the power lever is redundant electric [rheostats]. Electric fuel pumps are also required to provide positive fuel pressure to the two engine high pressure pumps. Two pairs of airframe electric pumps (so four pumps total, though the engine can run with only one of those four operating. The engine has two alternators, and the airframe has two independent batteries.

I hope to be test flying the second prototype within the next few weeks....

Interesting stuff Pilot DAR. Good to see that this engine is progressing.
Does it use solenoid or piezo injectors, and if the latter, what is the anticipated life of them?

Has any ballast been required to balance the Beaver with the current installation, and if so, would a fuselage plug behind the wing be possible to avoid this?

I can't answer what type of fuel injectors are used, but will ask. I have reviewed the RED documents, and they do not say.

As for the balance of the Beaver, it's actually better with the diesel installation. The Beaver was initially envisioned as using the Gipsy Queen engine:


https://cimg9.ibsrv.net/gimg/pprune....9fd240fdcf.png
(credit AOPA Pilot, April 1988)

The choice of the P&W R985 was made wisely, but perhaps too hastily. It was positioned too far aft on the airframe. The result was that original Beavers tended to be too far aft C of G. This has been a particular problem when on floats. I was involved in the test flying and approval of the modification to move the engine 9 3/4" further forward on the airframe, which moved the C of G forward, and allowed carrying a proper load in the back. I did very detailed W&B analysis on that configuration, including every plausible loading configuration. That understanding of the too far aft characteristics of the Beaver gave me great confidence in this new installation. Though the RED A-03 is heavier than the R-985, the MT prop is much lighter. The net difference is about 150 pounds heavier, at a slightly more forward fuselage station. This put the Empty C of G just where it needs to be for the Beaver.

I have flown the first diesel Beaver with full fuel, the boss in the right seat, and three 45 gallon barrels of water in the main cabin - still climbing at 600 FPM through 16,000 feet. The plane handled perfectly fine.

On the other hand, the Turbo Beaver does have a fuselage plug at the cockpit, as although the engine is placed well forward, it is also much lighter, so the fuselage had to be lengthened to maintain the correct C of G range.

Is that all you are going to give us?

I want more! (I can't type 'we' - I was told off yesterday for answering for other people)

Much more - this is fascinating stuff - detail - as much as you can manage

Please - keep typing ...... until you fingers blister

Like :ok:

Pilot DAR, as Deep Throat said, thank you for such a detailed description and please keep the info coming. Its fascinating how it has taken the Red V-12 to finally get the Beaver C of G in the right place after 75+ years.

Is there any possibility that we could see new-build Beavers to go with the new engine?

The second test "RED Beaver" ("SBN") is nearing readiness, it's being wired now. As things become, it's behind schedule. This can, in part be attributed to some careless flying, resulting in accidents, and taking staff time off the RED Beaver project, to recover damaged airplanes. I hope to be flying SBN in the next month or so. Based upon my extensive flying in SBA, I know what I'm looking for in development. SBA's untimely crash certainly delayed some development I had underway at that time, though in a happy way, we learned some things from the accident, and it has afforded us the opportunity to build SBN with improvements which should allow it to be saleable as a certified RED Beaver after STC approval - though that's still a year off. I'll have to conduct both very cold and very hot testing, so at best, we complete during next summer.

I witnessed more engine systems testing at RED in Germany last spring, and also met with the staff at MT Propeller to optimize our propeller installation on the Beaver, so we don't always need a flying airplane to advance the project. It is certainly planned that SBA will be repaired, and returned as the second test airplane, though that is not the priority just now.

As for brand new Beavers, I opine not. I'm presently working with the DHC team on Twin Otters #999 & #1000. And DHC is ramping up to fill customer demand for the 415 waterbomber. I doubt that the market for brand new Beavers could attract them away from those programs. Sealand, as well as a few other shops are great in completely rebuilding the Beaver, so the market will have to be satisfied with those airplanes - with RED diesel engines!

No criticism just curious.
Is Fadec really necessary?
A diesel engine is pretty bullet proof. and now with Fadec it is vulnerable to an electrical failure.
Just thinking of the joys of deep bush ops in the winter.
Also FADEC probably = $$$
Nice looking aircraft, performance looks impressive and my birthday is fast approaching.

Yes, FADEC $$$$! But, that's the way that the engine is certified. I too appreciate the simplicity of a purely mechanical diesel engine (my excavator is so equipped). But, FADEC allows optimizing power and fuel economy, as well as making the engine operationally simple. The FADEC does everything, after you tell it how much power you want - single lever. Though I'm used to airplanes with many levers, I see the world going toward single lever simplicity. This is actually creating a little too much simplicity for the Beaver, and we're designing around this total simplicity to optimize a few things (like being able to command coarse propeller pitch to make the glide better - sort of feathering, but not totally). That's the next phase of my testing.

When I see the data stream from the FADEC, and how an emailed file can further optimize the engine operation, based upon my observations while testing it, there's something to it! I don't see us ever going back to complete mechanical diesel engines for airplanes (nor most other machines for that matter). FADEC is just becoming too mainstream. My first few film cameras did not require a battery (other than maybe for the light meter). Can you think of a camera which does not need electricity now? Things change....

Yes, I have flown -40 a few times. The lowly Lycoming did what I needed it too. The RED diesel will too - as long as it is preheated to the minimum start temperature. We'll be taking SBN somewhere very cold this winter to test this!

Pilot DAR, in your post 29 is a scan of the development of the power plant choice.

Would I be correct in assuming that the missing words at the bottom read something along the lines of " Design it so that the wings don't come off, even if you bounce it off a glacier."

Ha, fair enough!

I found the continuation of the text I quoted in part:

I have little knowledge of the Stinson SR-9 mentioned, other than to say, that as a teenaged camper back in the early '70's, I was flown into summer camp once in one (all the other times Cessna 185's). That one Stinson suffered a fatal crash very close to where we were canoe tripping one summer. Beaver's are tough!

It's such a wonderful project, as I recall there was a Mercedes V8 diesel that was also previously used as an aero engine. I was considering buying one that I found at one point up for sale on Craigslist here in the sw US. It was a technical school unit that was up for sale, sorry I didn't jump on it at the time.

As is always the case there are pros and cons for axial flow versus eccentric reciprocating engines. With which we can lump in radials in the same category.
High compression ignition compression engines run lower EGT's which is good, turbo charging gives the ability to introduce more oxygen for combustion and develop more power. The turbos must be huge.

To achieve the correct stoichiometric ratio on a diesel more air (oxygen) is required than fuel per stroke - this is why a diesel has higher thermodynamic efficiency than a.gasser. i.e it uses less fuel per stroke.

I love the idea of using a compression ignition engine, but would be more inclined to consider two in-line V6 diesels with a coupling between the two with a mechanical bypass to the prop gearbox to allow for actual redundancy. Respectfully I would not wish on my worst enemy any type of reliance on the other bank of an engine that is mechanically attached to my good portion of the engine to get me home. Change my mind.

Having done a number of partial, and a few full engine shutdowns in flight of the RED A-03 engine I am impressed. It's a better arrangement in a single propeller airplane to have two sources of power to the propeller than only one. Yes, there are still mechanical vulnerabilities where the power from each bank of the engine joins to become one, but losing one cylinder in a V12, is better than losing one on a radial 9, and losing half a V12, is better than losing all of a radial 9.

In my flying career, four complete engine failures have put me on the ground. In hind sight, non of those I experienced would have put me on the ground had I been behind a RED V12, the six would have got me home. For my experience with engine failures (I have flown GA for 50 years, and worked at a piston engine overhaul shop for ten), in most cases, the things which make an engine stop producing all power without warning are usually not crankshaft/gearbox/propeller. Some yes, but not many. For the engines I have flown behind, and saw come into the shop, the truly mechanical failures to be gave the observant pilot and maintainer some warning. A temp going up where it should not, a pressure going down, running rough, or making metal.

I have flown both multi engined airplanes (with a propeller on each engine ;)), and multi engine helicopters - with only one rotor system. So, we'll have to consider the RED Beaver as having improved safety redundancy along the lines of a multi engined helicopter - not truly two independent power sources, but better than only one.

In the mean time, when the engine is running correctly (as the RED Beaver did when I literally flew it across Canada), is was more powerful, and burned less, of a lower cost, more commonly available fuel - what's not tl like about that!

We're working on the flight permit application for the second test RED Beaver, and I hope to be flight testing it in the next month or so...

looking forward to seeing the progress, I was in YBL when they were prototyping the mounts. asked about it and was told "its top secret if we tell you, we gotta kill ya" LoL. I then looked at it and said thats the V12 diesel innit, looks at feet looks up,yup! I think this could bring a resurgence to the Beaver so long if its half the price of the turbine.

Test RED Beaver #2 (SBN) is nearing readiness for test flight. I hope to be flying it in the next month or two. #1 (SBA) is planned for return to service, though that's not top of mind with Sealand at the moment, as they have yet another engine conversion project on the near horizon!