# Non- Biased Engine Reviews -Viking

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#### proppastie

##### Well-Known Member
Log Member
The engine is in a Tailwind
yes but any guidance from anyone on these issues might help as a point of reference.....should this information be provided to the customer considering safety aspects?

#### BJC

##### Well-Known Member
HBA Supporter
My history in this forum has been very light in terms of comments due to the fact that there are so many "experts" that try to tell me everything I should know, almost every time something is stated.
As I continue down this experimental road I would be happy to share experiences. I just will not put up with the "back seat drivers". If those folks haven't done what I am doing then please don't tell me what I should be doing. I will be happy to provide information and receive information. I just have to find the correct person to ask.
HBA is no different from the bunch of guys (and gals) who gathered behind my hangar for coffee this morning. Each one has an opinion, that he/she thinks very highly of, and is eager to share it in conversation. The trick is to separate the good information from the BS. That get easier to do once one gets to know the others in the conversation. This morning, Steve (working on his 27th homebuilt, has one going into the Smithsonian Air and Space Museum) was coaching a neighbor, who is assembling a WACO Taperwing kit, on how to splice the leading edge plywood skin. The best information available on the subject; everyone listened.

Stick around. Share what you are doing. Teach others. Learn from others. Retain the good stuff. Ignore the BS, although, sometimes, the BS in Hangar Flying can be fun, too.

And to everyone: I encourage you to fill out the “About” fields so we can more easily learn about each other.

BJC

#### BoeveP51

##### Well-Known Member
Does Jan offer guidance on these issues other than the recommended temp. say inlet/outlet sizes etc.? .....or does Zenair?
Yes, Jan did offer input to the issue. He recommended a larger input. This was not a simple fix as there would be major cowl changes. I was going to do it but fate stepped in and made me change it sooner rather than later.

#### Arkan

##### Active Member
This all very interesting, Viking, AeroMomentum, and other alternative engine sources do have some valid points. How do we advance aviation technology without trying new or alternative systems. Now a few on here know I don't fly, not from a lack of desire but from a lack of resources. But I love aviation, and enjoy the challenge of design. So that is what I do. Data is definitely needed, if I believed passionately enough in my own product, all would place it to the test, share my testing data.... give me accurate dyno testing results, and set several of the engines on a test stand and run them at full power until they failed and record how long they lasted. If I upgraded any part for reliability, make sure it is test in the same manor, these kinds of duribility test and sharing this data with your customers, gives them piece of mind and if your product is good, then it helps sell the product. An if there is an issue with one of your engines, go find out the cause, contact the customer, ask to inspect the failed engine. And if you have major failures, then report it, do a failures per hours flown report, the cause of the failure, how to avoid or if a correction is need, the contact the customers.

I say this because I have been researching engines for a design I am working on, and finding this kind of data is impossible. I have even poured through FAA reports, still no data. Anyways, I am not going to speak out for or against any company or their product, but if I am putting my life, or the life of my friends and family in the air, then I want facts and assurance on the safety of the power plant I am flying behind.

#### Geraldc

##### Well-Known Member
and set several of the engines on a test stand and run them at full power until they failed and record how long they lasted
Aeromomentum have done this by using airboats as test beds.

#### proppastie

##### Well-Known Member
Log Member
Aeromomentum have done this by using airboats as test beds.
their own boats or were the customers testing the un-tested products?

#### Arkan

##### Active Member
Aeromomentum have done this by using airboats as test beds.
that would be a good test for them, I was thinking more of a stationary stand. Mount and engine with a prop, run it up to take off power and let her run until she breaks.

#### rv7charlie

##### Well-Known Member
their own boats or were the customers testing the un-tested products?
That phrasing kinda smells like 'when did you stop beating your wife'. ;-)

My personal preference is to see it as letting potential a/c customers see independent, real world verification of durability & reliability. That's very different from using customers as the actual test cell, as has happened with some vendors.

Doing thousands of hours on a test stand just isn't going to happen in our field. It's not even happening in the certified aviation realm with its astronomical cost of acquisition; at least not these days, with piston powerplants. The ROI for the vendor just isn't there.

#### proppastie

##### Well-Known Member
Log Member
That's very different from using customers as the actual test cell, as has happened with some vendors.
That was what perhaps the poorly worded post 166 was about......Who are the "some vendors" ....

#### Geraldc

##### Well-Known Member
their own boats or were the customers testing the un-tested products?
their own boats or were the customers testing the un-tested products?
from Aeromomentum website."
We have been using these engines in boats and airboats since 2008 and have installed hundreds. These boats have been delivered all over the world including the US, China, Brazil, Russia, Pakistan, Australia, South Africa and many other countries. Many are used for tour and rental operations that use them hard and cannot tolerate down time. Only after years of experience with these G series engines have we developed our aircraft engines."

I am on no way associated with the company.

#### Arkan

##### Active Member
My policy is if you don't break it you don't know where the weak points are. You design an aircraft you intend to sell,,,, start building and start dropping them. Drop it 100 ft on its, nose, drop it flat. Send it at a steep angle into the ground. Find the weak spots, find where it is going to break, find where it fails, this is how you improve your design, this is where you begin to make better products. Okay I will step off my soap box.....

#### Voidhawk9

##### Well-Known Member
HBA Supporter
Drop it 100 ft on its, nose, drop it flat. Send it at a steep angle into the ground. Find the weak spots, find where it is going to break
If you build an aircraft strong enough to survive all of that, it will be heavier than a main battle tank, and will never be able to fly.

#### Arkan

##### Active Member
If you build an aircraft strong enough to survive all of that, it will be heavier than a main battle tank, and will never be able to fly.
it is not about making the aircraft survive, it better understand how when and where the frames breaks and building it so the pilot and passengers survive, or at least have a better chance of it.

#### aeromomentum

I would love to run one of my engines at full power until it fails. A customer (airboat) went 4000 hours. Admittedly, it was not always full power. But also it had very limited maintenance. So 4000 hours at full power with regular oil changes should be possible. Assuming 6gph (on our 100hp at full power) and $3/gal the fuel alone is$72,000.00. We have 8 versions with most being more powerful and thus using more fuel. So about $1,000,000.00. Just for the fuel. But this is way more than what is required for certified aircraft engines. According to §33.49, engine certification endurance requirements are 150 hours total test run time! Of this 150 hours only 105 hours is at max power. We have done more than this and inspected for wear. #### BBerson ##### Light Plane Philosopher HBA Supporter The certified engine needs to test run again for each engine-prop combination or measured with instrumentation. No requirement for experimental but the pilot should understand and be prepared for dead stick anytime, even after 150 hrs. #### proppastie ##### Well-Known Member Log Member We have done more than this would that be your company or a compilation of air boat customers......if your company.....any issues especially with the reduction? 105 hr max power with a test club no issues is very impressive. #### Arkan ##### Active Member I would love to run one of my engines at full power until it fails. A customer (airboat) went 4000 hours. Admittedly, it was not always full power. But also it had very limited maintenance. So 4000 hours at full power with regular oil changes should be possible. Assuming 6gph (on our 100hp at full power) and$3/gal the fuel alone is $72,000.00. We have 8 versions with most being more powerful and thus using more fuel. So about$1,000,000.00. Just for the fuel.

But this is way more than what is required for certified aircraft engines. According to §33.49, engine certification endurance requirements are 150 hours total test run time! Of this 150 hours only 105 hours is at max power. We have done more than this and inspected for wear.
I am impressed, AeroMomentum. I know this is supposed to be a thread about a different engine company. I have a thread called Project Bush Demon. I am designing a STOL bush plane. I would like to ask some questions there if you if I could. My thread is totally a design thread, I don't have a pilots license, or funds to build a plane. I am working on sketching designs, and ultimately blue prints for a STOL back country bush plane. I believe I found the power plant I want to base those designs on, and would love your input.

#### Voidhawk9

##### Well-Known Member
HBA Supporter
No requirement for experimental but the pilot should understand and be prepared for dead stick anytime, even after 150 hrs.
True of certified engines as well. 'Infant mortality' isn't unheard of even with these old, proven engines.

#### Oliver

##### Member
[...] A customer (airboat) went 4000 hours. [...]
Hello Mark,

You keep stressing how you are using airboats as a test bed. Hundreds of them, for thousands of hours!
I was never able to independently verify this for the AM15, which I had bought from you, even though I spent a considerable amount of time trying to find manufacturers or owners of airboats who are using your engines.

Now, I am certainly not saying that your claims are false, but I am wondering to what extend they are true!?

I believe you launched the AM13 only 2 or 3 years ago, if I am not mistaken. What kind of testing went into it before you started selling it to aircraft customers?
The page for the AM20T is (still) showing the engine sitting on a pallet: AM20T
The AM20 and the AM24 only have ‘Information coming soon’: Untitled Document

The information on your airboat website is also rather on the ‘light’ side. The AM20 and AM24, as well as the ‘low profile versions’ are not offered at all: airboat engines
No videos, no pictures, do data, besides of a few close-up images.

I am sure that potential customers would like to see some hard evidence for the amount of airboat- as well as aircraft-testing, that went into your engines – not just in general but broken down by variant.
Personally, I would also expect to see on your FB posts like ‘Gator Airboat Rides have successfully accumulated 2,500 hours with three of their airboats, which we are using as a test-bed for our new AM20T aircraft engine’.
But, again, nothing. No pictures, no videos, no data, just nothing.

I hate to rain on anybody’s parade, especially publicly, but you and I had this discussion over the course of several years and I think that potential customers should be aware of the lack of test-data as well as the quality and completeness of the fwf ‘kit’, before they make a decision.
I also believe that hard test-data is in case of Aeromomentum particularly important, since you are not only significantly modifying these engines, compared to a stock Suzuki, but since you are also manually assembling them in your shop with (primarily) aftermarket components, which might or might not be of the same quality as Suzuki OEM parts.

Oliver