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Mark Discusses Advantages/Disadvantages of Different Engine Technologies
I visited the aeromomentum.com website and found an interesting write-up by Mark, the owner of Aeromomentum. In it he discusses the engineering choices that led him to choose the line of Suzuki engines that he uses for aircraft conversion. Here's a link:
Replies to This Discussion
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Permalink Reply by Mark Kettering on
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Readers should also know that Oliver never even got to the point of finishing the installation of his engine let alone starting it, taxiing or flying. I am not really sure why he gave up. Maybe it was that his project has taken many more years than he intended, he was deterred from outside pressure, his situation changed to due to unrelated things, etc. In any case he had no first hand operational or flight experience of the Aeromomentum engine of any type.
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Permalink Reply by Oliver Reik on
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Hi Mark,
Yes, my situation at work and that we really wanted to finish the Zenith were the final straws that broke the camel's back.
This being said, we would have never sold it at a huge loss (we sold the entire package for only $9k to be exact and the buyer hasn't even picked it up yet as he is trapped in Canada) if the fwf 'kit' would have been reasonably complete and of decent quality.
You claimed in the discussion on Homebuiltairplanes that things have changed for the better and I want to give you the benefit of the doubt.
I would however still advice potential buyers to not make the same mistake we made and pay for everything in full upfront. Also, don't send a check based on promises but actually go and see(!!!) the kit as well as completed(!!!) installations in person. What is acceptable for one guy might not meet your expectations.
The only flying Zenith with an AeroMomentum, that I am aware of, is the one built by Kevin Perreau in New Zealand. He is also on this forum and might be worthwhile contacting.
Oliver
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Oliver, Yes we always work to change things for the better. From our past conversations, you did receive everything and before you were actually ready to use them. From past conversations, everything worked. Unfounded and unsupported speculation on your part is just that. Yes, the cowling took way too long but you did receive it before you needed it. Now that we are on our forth supplier they are being delivered when ordered without delay. I am very sorry for this but for me, what really hurt was the long illness and death of one of the suppliers that was a friend for over 20 years. I also offered you more than what you sold the engine for. Much less loss than Rotax would have offered for a 3 year old Rotax.
If you look, you will find a bunch of Zenith aircraft flying with our engines including CH-701, CH-750, CH-601 and CH-650. Yes there are videos. Again, I am not a promoter at this point since I am busy with engineering and testing. As we are finally getting all of our supplier issues worked out in our covid impacted supply chain we will start promoting our engines.
For your entertainment, here is a link to a CH601 that recently flew.
A picture of this Zenith CH601 is attached. Please note that this aircraft was first flown with a popular European engine that was replaced with our Aeromomentum engine for better performance. And it did not disappoint.
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Mark,
I am surprised that you want to have another public discussion about this, but that's of course your decision.
As per my e-mail, sent to you on January 5 2021 these items were still missing:
- Spinner + backing plate
- Prop spacer
- Nostrils
- O2 sensor
- New plenum with shorter tubes and hoses
- Re-positioned coolant reservoirIt doesn't matter if I needed the parts or not - we paid for everything in full 3.5 years (!!!!) earlier. A total of $16,690!
As of today, I still have neither received the nostrils nor a properly fitting engine mount and cowling. Pretty much all auxiliary components are just a collection of cheap aftermarket automotive components and not exactly what I would consider a kit.
Also, I offered you in January 2021 to buy everything back for 60% of the original price or $10,014. Personally, I think this was a very fair offer, since you clearly breached our contract by not delivering a complete, properly fitting package for our Zenith CH750 CruZer, even though you had 3.5 years to make things right.
You however offered me only 50% of the total amount and wanted me to pay for shipping and insurance to Florida, what would have cost at least $1,000. Additionally, you reserved the right to inspect the engine and to make deductions, if you would have found any issues with it, what would have been at your sole discretion.
So, best case scenario would have been $16,690*50%-$1,000 = $7,345 if (and that's a BIG if) you wouldn't have found any issues with it.
Please let me know if you want me to refresh your memory, I can gladly post our e-mail communication.
I honestly (really!!!) hope that you managed to change things for the better but am somewhat skeptical that the changes go much beyond the replacement of the unlabeled, no-name fuel pumps with brand name components.
I don't want to hurt your business but also don't want other builders to find themselves in the same situation we did.
I think you should grab your phone and make a video of an actual, recent installation and go over what comes with the fwf kit. The last (shaky) video of your very own 701 is from 2019 and the plane doesn't even have a cowling installed! Doing this might take a day but will save you a ton of time in the long run, as you will have to spend less time answering customer's questions and concerns.
I think that it is generally a good idea to speak with other customers and to have a look at their installations in person!
In case of AeroMomentum, I however think that it is an absolute must: I have been disappointed too many times by massive delays, excuses (it's ALWAYS somebody else's fault), empty promises, lack of documentation and low quality components.
Oliver
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Oliver,
You did not receive a spinner and back plate since you did not order or pay for one.
You did not receive a prop extension since you did not order or pay for one.
I am very sorry that my cowling supplier died and the molds were lost. I offered to exchange your cowling with a new one when the new supplier was delivering. They are now delivering.
According to our records and packing list, you received an O2 sensor. If there was a problem with yours you could have returned it for free replacement.
I offered to exchange the intake tubes and plenum at no cost but you never sent the old ones to me for exchange.
I offered to exchange the re-positioned coolant tank to you at no cost but you never sent the old one to me for exchange.
Yes we have changed and improved things in the last 3+ years. So has Lexus, BMW, etc and they do not offer to upgrade like we did for you. They will also not give you free stuff that you did not order or pay for. Yes, our FWF packages have changed both in price and what is included.
I have been absolutely honest in our supplier problems and I always do everything in my power to rectify the solution as soon as possible.
As I said I am not a big promoter, picture taker or video taker. Now that we are starting to get our past supplier issues solved this may change. Thanks for your advice.
If anything I have said is not true please contact me privately and I will publicly provide a correction.
Yes, any returned parts must be inspected. Did you suspect there was a problem that would have reduced their value? Also a lot can happen even in shipping.
Mark
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Mark,
I am genuinely shocked about where you decided to go with this, particularly since your apparent honesty is your key selling point and helps you get away with the wildest excuses.
Anyway, let me respond to your claims.
"You did not receive a spinner and back plate since you did not order or pay for one.
You did not receive a prop extension since you did not order or pay for one."
Not true. Please check the e-mail you sent me from your Yahoo account on July 6 2017 at 2:36 pm.
I think the statement "Sounds good and yes you get the free prop and spinner." doesn't leave much room for interpretation.
Screenshot of your e-mail: Aeromomentum_Prop.jpg
"I offered to exchange your cowling with a new one when the new supplier was delivering. They are now delivering."
Oh, this is news to me. I must have missed that. Since the old cowling is still sitting in our hangar, I would like to ask you to have it picked up and to ship a new cowling at no cost for us. I purchased and paid for a cowling that fits a Zenith CH750 CruZer reasonably well. So far I haven't received one yet. Also, please add an engine mount that put the engine at the correct height.
"According to our records and packing list, you received an O2 sensor. If there was a problem with yours you could have returned it for free replacement."
The packing list didn't even have the oxygen sensor on it: AeroMomentum%20packaging%20list.jpg
You also never questioned my claim that I haven't received it yet. It was however (finally) shipped early this year, so we are good on this now. The only component, I am aware of, that we never received are the nostrils.
"I offered to exchange the intake tubes and plenum at no cost but you never sent the old ones to me for exchange.
I offered to exchange the re-positioned coolant tank to you at no cost but you never sent the old one to me for exchange."
Not true. I sent you on Jan 17, 2021, 7:27 PM an e-mail to your Gmail account with the tracking number of the package. Screenshot: AeroMomentum_return.jpgThe tracking number has expired since but when I checked late January, USPS showed it as delivered. You also never complained that you didn't receive it. USPS allows you to check old tracking numbers for a fee, though.
"Yes we have changed and improved things in the last 3+ years. So has Lexus, BMW, etc and they do not offer to upgrade like we did for you."
I am not aware of any "upgrades" that you provided. You merely inched a tiny bit closer to delivering a functioning engine package. I never heard of Lexus or BMW delivering cars that have the engine sticking through a not even remotely fitting hood.
"Yes, any returned parts must be inspected. Did you suspect there was a problem that would have reduced their value? Also a lot can happen even in shipping."
I am not aware of any issues with the engine. And yes, there would have been a tiny risk for you that something might have been damaged. This still doesn't even come close to the risks we took by paying for everything upfront and for being patient with you, what caused us significant losses, financially and timewise.
You also don't seem to realize how generous my offer was (I feel like a fool for this now) to buy everything back at a significant discount, giving you the opportunity to quietly walk away from this!? Many others would have already sued you a long time ago, most likely forcing you to pay a full refund, plus your legal fees.
Screenshot of my offer and your response: AeroMomentum_Offer.jpg
With best regards,
Oliver
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Oh Oliver, Returns never work that way. You always need to return it first and then get the refund. This is universal. If an engine has been sitting for 3 years it needs to be run regularly or re-preserved every year. Did you do this? You told me that you did not. How would you expect us to buy back an engine without inspection that by your own statements had not had the correct preservation? This is fully on you.
So now you are saying that we did ship you an O2 sensor? But in the above post you said it was still missing. Are you currently missing the O2 sensor?
You did not order a prop extension. Yes this is true.
Originally the spinner was not part of the offer. You then pushed to get more for free and I agreed. My mistake! I did owe you a spinner. This is the only part.
Did you send me the induction tubes like you recently claimed? Did I send you upgraded tubes? Do you now not have any tubes? I am not sure what you are saying since it seems to be self contradictory.
We are flying our Zenith 701 with the original induction tubes, plenum, radiator and coolant tank. They all work very well. But we always strive to make things better so they are called upgrades.
Oh Oliver, we had many phone conversations about the mount and cowling. Many others have successfully used the same mount we provided to you. It works as has been proven over a dozen times. I am not sure why you have an issue here but no one else with the same mount has your issues. You also measured your mount to confirm it was the same as all the others.
The original cowling does install quicker with the add on nostrils. But again we talked about this many times and you agreed that you would do the minor modifications for it to work for your installation. At that time I really wanted the original cowling back so that I could take new molds off of it to replace the lost molds. Now that time is past and we have new molds. And you said that you would make the original cowling work.
Like all offers there are time limits. For the next week we have an offer of a free header and radiator with an engine purchase.
So to recap:
- Spinner + backing plate
My mistake, sorry. Have the new owner contact me.
- Prop spacerYour mistake. You did not order this.
- NostrilsWe made an agreement that you could exchange to the new style (you pay shipping) but you would need to wait or you could do the minor modification. You rejected the exchange offer and agreed to do the minor modification. This is on you.
- O2 sensorYou have it as you have now confirmed, I think...
- New plenum with shorter tubes and hosesYou have a working plenum, etc. Did you send us the older style? Did you receive the newer style? Please confirm.
- Re-positioned coolant reservoirNot needed but we did have a limited offer to exchange.
Best regards,
Mark
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Also as we talked about in the past, you could use other cowlings from other suppliers. Our engines not only bolt to a Lycoming mount they also fit in most other cowlings including some of those made for Continental and Lycoming engines on the CH750. Other builders have done this.
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Hi Mark,
I wasn't able to reply to your last post, so I'll use this one.
I don’t know why you are doing this to yourself, you should have simply ignored Michael Moore’s link to Homebuilt airplanes. I believe we ended the discussion over there on a relatively positive note. Now you’re putting the spotlight on the issues we had as well as how they indicate deeper organizational, quality as well as documentation problems within your company.
That potential buyers have to believe your promises due to a lack of documentation because you’re "not a photo and video guy" doesn’t help either.
Potential customers can only guess what exactly they will be getting and what the fit and quality of these components will be, since your website doesn’t have much more than a list of items and a few pictures on it. No images or videos of a complete installation with the latest components, no aircraft specific details, just nothing.Based on our experience and considering the lack of information regarding the improvements that were made, I would therefore strongly encourage potential buyers to get in touch with existing customer and to have a look at their installations.
Anyway, these are of course your business decisions, so let me continue down the rabbit hole and respond to your claims.
Mark: “Returns never work that way. You always need to return it first and then get the refund.”
I think that you still don’t (want to) understand is that I never asked for a ‘return’, like of a pair of shoes in the wrong color. I instead offered you to walk away from a contract that you were obviously unable for fulfill. Yes, you delivered ‘something’ but certainly not a reasonably complete and fitting firewall forward kit.
Mark: “So now you are saying that we did ship you an O2 sensor? But in the above post you said it was still missing. Are you currently missing the O2 sensor?”What I said (s. my post above) was that as of January 5 2021 we WERE still missing the O2 sensor as well as some other components. I also wrote that as of today (now 4+ years after paying in full) I still have neither received the nostrils nor a properly fitting engine mount and cowling. Everything else seems to be there, albeit not in the quality I had expected.
Mark: “You did not order a prop extension.”I ordered a complete engine and fwf package. You only mentioned an (apparently mandatory) prop extension after I send you pictures of the cowling colliding with the engine in several areas. No word of a prop extension in the then-current installation manual either.
Mark: “Originally the spinner was not part of the offer.”Who would have thought that a spinner is not a part of a complete fwf kit!?
Mark: “Did you send me the induction tubes like you recently claimed? Did I send you upgraded tubes? Do you now not have any tubes?”I did not only ‘recently claim’ this, I also sent you an e-mail in January, including a tracking number. As per USPS it was delivered. Check the screenshot I posted above. And yes, you sent me new components, as I also posted above.
Mark: “We are flying our Zenith 701 with the original induction tubes, plenum, radiator and coolant tank. They all work very well. But we always strive to make things better so they are called upgrades.”Sure, if you want to fly without a cowling it probably works just fine. You only offered to send me the new plenum after it became clear that it is needed in order to be able to install the air filter. You also sent me the new reservoir only after some customers (like Andy in Australia, who ended up with a ruined engine) found it very difficult to bleed the coolant. You never sent a new radiator, what however might have been a good idea, since (at least) Andy and Kevin were having significant overheating issues, even though both are flying relatively fast aircraft, where cooling should be less of an issue than in a 750.
Like I said – you never provided any upgrades but merely inched a tiny bit closer to delivering a functioning engine package.
Mark: “Many others have successfully used the same mount we provided to you. It works as has been proven over a dozen times. I am not sure why you have an issue here but no one else with the same mount has your issues. You also measured your mount to confirm it was the same as all the others.”Isn’t this another troubling issue? I spend a ton of time installing it, taking measurements and pictures and discussing the issue with you. Still, you have no idea what the problem is. Since there is zero room for adjustments, this either is a design issue or and indication of significant quality problems. Our Zenith is built from a kit, the dimensions of our firewall are therefore exactly as designed by Zenith.
Mark: “But again we talked about this many times and you agreed that you would do the minor modifications for it to work for your installation.”This is correct, I agreed to some minor modifications. I did not agree to build a (stupid looking) scoop and several bump outs, to accommodate for the various collisions between the engine and the cowling. This also would not have solved the issue of the cowling not even remotely matching the shape of the firewall.
Mark: “At that time I really wanted the original cowling back so that I could take new molds off of it to replace the lost molds.”You must have spoken with somebody else about this. Considering how poorly it fit, I am however not sure if this was such a good idea anyway.
For those, who wonder what this is all about, some pictures of the issues with the engine mount and the cowling.Routing of the exhaust needs to be ‘adjusted’, supports fabricated:
The top of engine is around ½” higher than glare shield. Fabrication of a about 1” tall scoop on top of the cowling were the only solutions Mark and I were able to come up with, to make space for the engine:
Lamination issues:With the cowling centered on the prop shaft, the fuel rail collides with the cowling as well:
The shape of the cowling does not match the firewall. Mark suggested to force it in place, what would however have required a LOT of force and what was therefore not practical:
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Oh Oliver, I am so sorry. I had been trying to provide the truth and it seem that for you it is something different. I just want to be open and truthful with everyone.
Again, we never sold and you never bought a "a complete fwf kit!?". We sold FWF parts and still do. Some people buy more of them from us and some buy less. It is the customer's choice! Yes, you need to buy some standard parts from ACS. We mainly provide the stuff that they do not sell. It makes little sense for us to buy from ACS, mark it up and then sell it to you. Buy from them direct the standard parts and save.
At the time of your order we did not even have or sell prop spacers but this is a common item from ACS, DUC, Saber and others.
Yes, you said "were" missing but it implied that they "were" still missing and you were just repeating the previous claim. In any case I am just trying to get the facts straight and not add a bunch of third hand misinformation, falsely leading questions and reinterpretation of things we already agreed on.
The facts are you got everything you bought (except the spinner, my mistake!) and before you needed it. The cowling fits with minor modification and you agreed to do this. I provided you with added cost improvements for free and the parts you originally received are well proven to work when the instructions are followed.
We and many others have flown with a cowling and the original cooling system works perfectly when installed to our instructions and filled with coolant. The reason for the upgrade was to simplify the system and make it a little harder to install it wrong. We made it simpler to fill and mount and made the total tube length less and reduce the system complexity. No longer did you need to mount the tank on the firewall with long plumbing. The mounting location of this tank and the routing of the hoses are important for how easy the system was to fill. This also slightly reduced the weight of the cooling system.
The reason for the upgrade on the intake system was because the original system was designed for peak power at 5800 rpm. Later, once we started offering the high power upgrade and needed to retune the intake for possible use at higher RPM. When we did this we also made it a little tighter to the engine. And since you were having issues we upgraded you for free. The original system was actually a little better at cruise RPM economy but this difference is in the noise.
The mount works for over a dozen other builders perfectly. I have no idea what you did different with the mount and tried to work with you to both make sure it was not a mis built mount and to find out what went differently in your installation that did not happen in any other installation. The holes on the mount (to the firewall) are not predrilled and can be adjusted a fair amount. Keep in mind that depending on the kit serial number there can be a 10mm difference in the holes on the firewall.
In picture one, there should be a ball joint that is a standard ACS part. This was said to you and it is in our manual that is online. The ball joint allows the exhaust to point out correctly.
In picture two, the engine is a little above the top of the firewall. The cowling takes this into account as per the drawing. The cowling bumps up. Yes your engine is a little high but I think this is because you miss drilled the holes on the engine mount a little. Also even with prepunched kits we have seen over two degrees variation in firewall angle between builders and the builder needs to compensate for this when mounting the engine mount to the firewall or the engine could be too high.
Picture 4 is a complaint about the cowling not being perfect. It is not. But it is very good, very light, very strong and very cool anyway. With most composite parts there is always a little rework.
In picture 5 it shows the cowling sitting on the fuel rail. But regardless, this is the minor speed bump that you told me was fine and that you were fine with adding. We even talked about how to do it and how some cars had them for style. It seems that even when we agreed you want to go back on this agreement and complain.
Picture 6 shows the cowling not conforming but this can be pushed into place with one finger! Yes, I was not happy when I saw this but then I saw that it was a total non issue when the cowling was attached. There is plenty of flex. There are actually a lot of aluminum parts that are just flexed into position and there are actually some cowlings made from flat aluminum that are just wrapped into place each time the cowling is closed. The non molded Zenith windshields are just wrapped into place. This is so simple with this cowling. But our new cowling is better. This is called kaizen in Japanese.
I think this discussion shows that I am very willing to stand behind my products (free upgrades to you), admit my mistake (spinner), keep improving my products, work with all of our customers, find solutions to any issue and provide actual facts.
Mark
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WOW!!!
I am seriously considering an almost completed CH 650 kit. About all it is lacking is some minor final skin panels riveted, an interior kit, avionics, and an ENGINE and FWF KIT!
I have considered Jabiru (Gen 4 seems to have fixed all of the identified problems - - but??), Viking, Aermomentum, and ULPower. This ongoing, very public feud between Viking and Aeromomentum has been very helpful in my decision process.
It looks like my choices have been narrowed to Jabiru or ULPower. I'm leaning towards UL.
Oliver, great record keeping - - -
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Hi Joel, ULPower, especially, makes a great engine with modern fuel injection. The USA distributors are also fantastic and much better with customer relations than I am!
Best wishes on your build with whatever engine you choose, be it Rotax, ULPower, Viking, Corvair, VW, Lycoming, Continental, Jabiru, Aeromomentum or any other! You have plenty of choices!
Mark
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