"Post-sale support will be limited from seller...." Kind of a PITA when the seller is the only entity that understands the engine.
Yup…sounds more like a 172 airframe for parts than a flyable airplane.
Then why did it take years and years to get the STC? Are you saying the STC was processed in a commercially reasonable fashion? Because that's not what I got from reading about G100UL.
My bad. I thought you were referring to the OP V8 article since there was no quote in your post. Not the G100UL.
As I explained in Post 18 the G100UL STC time frame looks ballpark based on what is publicly out there. Don't quite follow what you mean by "commercially reasonable" in the context of a certification process.
Seriously. Do they think they'll bet dealing with a different FAA for that?"We are selling to make room for developing a hybrid engine version."
For what, an aircraft?
Maybe they're going to try and put an O-320 into a boat this time? However, they did mention a 414 in the article....
The FAA isn't a roadblock; certification is a road, and when you get with the FAA, that road is clearly (and I do mean clearly) defined. You build this, you test it this way, for this long, we [FAA] inspect the bits. Developing and certifying a new [for example] large commercial turbofan family, the GE Aerospace GEnx series, cost upwards of two billion dollars.https://airfactsjournal.com/2022/10/the-20-hour-cessna-172-experiment-update/
I found this article particularly fascinating. They found a way to address the leaded gas issue. Plus reduced operating costs, emissions and noise. You get one guess what the roadblock is.
I read it somewhere, but I believe it was limited closer to 220HP in the C172 as that was the highest power available in a certified model. Flat rating an engine capable of producing well over double that figure should ensure that you don't have to be turning 6K rpm in order to develop the necessary power.
True enough. I still see no values listed.
Please explain more….. what is the difference you mention and why an auto engine cannot be a variable replacement.WW2 aircraft used auto engines. All certified diesels are auto conversions……. What’s your point? Please reference technical data so to get a better understanding of your statement.
The listing states it comes with service manual and software and any auto mechanic withe ECM knowledge can work on it…. Just as any modern car.
"We are selling to make room for developing a hybrid engine version."
For what, an aircraft?
Looks like the October article in the OP was merely a pre-sale marketing ploy to gain some coverage.
sorry you got that out of the article …. Don’t see how how you came to conclusion about it being about “beeyotch”ing……article was was requested to update earlier article and it’s was intended to be factual about progress, and magazine editor found it factual and without such bias. Sorry you somehow came to such an opinion.
Actually, it’s anything but a scrapper from practical sense. It flys better than any c172 and fun to fly. A couple of guys built a couple of hundred hours on it and are now flying for the airlines as a result. No reason it can’t continue. Selling it exposes builder to above average liability risk without practical mitigation, and really only reason for scrapping after flight testing is completed.
No, seriously, we are not that foolish. Fact is the project started out as an engineering challenge and a fun project. And it was. Our goal was to take this design, learn a lot, and evolve it to hybrid as automotive technology development allowed. We don’t have enough $ or time to both develop the engine and fund cert costs, so hybrid will be just be personal experimental aircraft. Our projected performance and numbers for a hybrid are pretty impressive and always exciting to see how close we come to projections once flying.
Maybe, but it doesn’t appear that way to me.
Examples?
It's tough enough these days finding an A&P willing to do the yearly condition inspection on an Experimental Amateur-Built aircraft. Going to be tougher with an orphaned auto engine conversion.
Sorry you missed article’s description of main issues project faces…..it is not the certification process at all. It was regulatory leadership preventing us from developing the design in the first place. As a former DER, the cert process is , as you say , outlined after negotiations and such, but one must be able to develop the design first. It sounds as you are ACO related and work with well funded projects using an array of DERs, both company and consultant types, that are essentially developer’s personal FAA once delegated. GA does not usually offer such options for small companies because of cost. It’s mostly a moot point as without FAA leadership at least being responsive, there’s little chance of getting anything meaningful done without resources to apply to FAA effort as well as development.
The performance, fuel flow and airspeed is depicted on posted inflight videos. If you believe we are doctoring the data and IAS, that’s your right. We tried using raw flight video to exhibit said data, including date and times WX conditions can be verified. Our data is not much different from exp aircraft using V8 engines. Depending on prop used and altitude, our cruise performance is 15-23% more efficient (FF/TAS) than original engine. We detailed posted proven data on website as well, but fuel cost assumed on site is a bit outdated but easily corrected with basic math. Again, if we ever decide to offer selling anything, we would post far more specifics as the design will be finalized. We don’t have a detailed spec sheet posted simply because design is still evolving. Our last prop design increased cruise efficiency more than 5% and we will be making more mods, so not sure what final data be if we continue developing but our goal was another 4-6% with prop and planned software mods.
Man, you're just a hater. A basic V8 will happily run continuously between 3,000 to 4,000 RPM for thousands of hours. Don't believe me? Just ask the automotive V8 in my boat (which has been doin' it for 20+ years), or the V8 in any Uhaul truck.
Interesting. That doesn’t sound like the goal that was stated in prior articles and website postings.
Diagnosing a fault in the engine electronics will be fun, too. You can get limited information from a portable OBD scan tool, but to really troubleshoot you need the big non portable system that the dealer service shops and better independent garages (but no A&Ps) have. Smaller shops and home mechanics diagnose by throwing parts at it, then drive it and see what happens... not a good idea in an airplane.
I’d like to see any logic at all that hybrid makes sense for aircraft. It only works in cars in stop and go traffic and hilly terrain. Neither of which occur in aircraft flight. And no, climb /decent doesn’t fit because A, it only happens once per flight, so it’s of extremely limited benefit, certainly not worth hauling extra motors and batteries around for, and B, you don’t get any extra energy out of the decent unless you power a generator, which slows you down, kind of counter productive in air travel, most people want to be going faster. It’s a bit like this
And they did that how? Regardless, while the magazine editor thought the article was factual, I base my opinion on the actual facts of the certification process which I found to be lacking in that article and in other posts. The fact you are moving forward from the 172 project is probably a good thing but it did not fail due to that certification process. Good luck with your new venture.
Based on my analyses of homebuilt accidents, auto engines have a much higher failure rate. About 22% of all accidents involving auto-engined-powered homebuilts were due to mechanical failures of the engine (either spontaneously or due to builder/maintainer errors, vs. about 7% of all accidents where traditional certified engines were installed.
No, I’m simply a realist and admittedly an owner of a GM LS equipped product with it’s second LS engine. You can talk to it if you like. Hour for hour it’s been the most problematic POS I’ve ever owned.
