Engine Choice

[Jon Matcho]

I stumbled on this post in a thread about a newly purchased kit with a Mazda Rotary 20B engine and find it quite a noteworthy read:

 

I have said this other places:  These canard airplanes are not good designs with which to experiment with engines.  They glide shallow and land fast and there are no flaps or good drag devices that you can use to assist in picking your landing spot and approach speed.  I have checked guys out in my Cozy and it is the rare person who can set up a decent off-airport landing approach.  It is so easy to be fast with no way to slow down.  What can happen is that the gear is somewhat fragile; nose gear collapses, canard digs in or catches something and the heavy engine-end of the airplane flips it over.  Also, energy dissipation in a crash is related to velocity squared.  If you land engine out at 100 vs 80 you would have 56% more energy to dissipate in a crash.  You can stall a Cessna in at 50 kts.  In my Cozy, a couple seconds of inattention in an engine-out pattern and I'm gliding at 100 kts--300% more energy to dissapate in the break-up of the airplane and my little pink body.

 

From time to time, I've had various little glitches with my airplane engines and believe me, I am not crazy about flying when there is any doubt about my engine.   Let me pose the case where your rotary is flying but you have a few problems to iron out.  You are sorting out water-cooling, PRSU, a very hot exhaust and non-standard carburation in an airplane that you hardly know yet.  This makes you much more of a test pilot than the guy who has bolted-on a Lycoming. The failure modes of a Lycoming are well-known and can be foreseen with ordinary care.  The failure modes on a rotary are more unpredictable.

 

People say "Well, a rotary will run for many minutes with no water."  Heck, I never want to get to that test condition.  And unless your rotary performs flawlessly, your wife and friends are not going to want to fly that airplane and you wouldn't ask them to.

 

Just some food for thought.  

I am all for truly new and improved systems, but I do appreciate this advice.

[TMann]

I am all for truly new and improved systems, but I do appreciate this advice.

Well since you have already expressed your opinion with regards to Rotary, I would be totally amazed if you were not on board with that post.

Why not reveal the source/author to put it in perspective?

 

I finally was able to contact the original builder of my Velocity. It was rebuilt and he only put 60 hrs on it.

Early on the engine threw a rod.

 

As the quoted post says "The failure modes of a Lycoming are well-known".

Indeed they are.

[TMann]

Why not reveal the source/author to put it in perspective?

 

Ah, I see who the original poster is and that does put it in perspective.

Sorry I didn't catch that earlier.

[Jon Matcho]

Well since you have already expressed your opinion with regards to Rotary, I would be totally amazed if you were not on board with that post.

My point was simply that I do indeed appreciate new technology as well as this real-world experience, data, insight and advice. "Food for thought" as Kent put it. I personally found it eye-opening enough that I felt compelled to re-share it with the community.

 

Personally, my engine of choice was originally to be a Rotary as you can see in my previously expressed opinions on this forum. For example: http://www.canardzone.com/forum/topic/16317-is-it-worth-it

 

I continue to be appreciative and in awe of those that have built and successfully flown rotary engines, diesels, and other auto conversions.

 

Why not reveal the source/author to put it in perspective?

Ah, I see who the original poster is and that does put it in perspective.

Sorry I didn't catch that earlier.

Rather than derail healthy discussion and debate into personal quips we'd all do better off keeping focus on the bigger picture of the community at large:

1. The Canard Zone's mission:  "Our community-wide goal is to encourage the building of safe canard-type aircraft, and to improve their popularity within the wider aviation community."
2. To get more aircraft flying, so far using non-aircraft engines has NOT been a catalyst.
3. Kent raises an excellent point, and made a very clear statement worth noting:  The canard aircraft design is not a good platform for testing one-off and unproven engine designs.  
4. The purpose of this discussion is simply to keep an eye open on all engine options, particularly those for which most all canard aircraft have been specifically designed for.

Feel free to share any data, information, even additional anecdotes for rotary engines, but anything resembling a pointed barb or personal attack against any member here needs to be checked.

 

Let's all build and fly canard aircraft.  That's what we do here.  How do we get more in the air?  How do we finish our projects?  What constructive advice can be offered.

 

Off my soapbox... thanks for reading. 

[TMann]

.....but anything resembling a pointed barb or personal attack against any member here needs to be checked.

I believe you are trying to convey your perception rather than my intension.

 

My comment was merely reflecting the fact that Kent's opinions on Rotary as an aircraft engine is well known and so the text came as no surprise.

Bill Welter is currently taxi texting his Rotary powered Long-EZ.

 

As far as posting any rotary relevant material .... I'll save that for the Fly Rotary group.

[Jon Matcho]

I'm sure anyone seriously involved with rotary engines is on the Fly Rotary group.  

 

Everyone is more than welcome to share information and insights, just don't make it personal.  The quote in the first post here stands along on its own merit, contains actual data, and is worth a read by everyone -- even those intending to fly Lycomings or Continentals.

[TMann]

I'm sure anyone seriously involved with rotary engines is on the Fly Rotary group.  

If they are new to this and are considering a Rotary as a engine of choice then yes, it would be imperative to join the list at www,FlyRotary.com.

Many who come here are not aware that this list exists as is for the support of those wishing to go this route.

If you want REAL statistics of issues, reliability, etc. of a Rotary, it is all openly discussed there with no bias or sugar coating.

 

For Canard questions, I would have no problem with the knowledge base here or on the other canard forums & lists.