Swift 100R gets ASTM Approval

[brien23]

Option 8. Use 100 LL
Option 9. There will be something else.


Hey, I’m an optimist!

High Octane Rating: The resistance of a fuel to "knock" or "ping" is measured by its octane rating. Gasoline typically ranges from 87 to 92 octane. Propane has an effective octane rating of about 104 to 124.

 

[737steve]

I've got a big emergency generator next to my house that runs just fine on it. Farmers around here used to use it in tractors. The storage and plumbing are where things get...interesting.
I think if liquid fuel is replaced in general aviation, it will be by electricity. Of course, that's just a guess.

 

[MackMooney]

serial hybrid would be nice. maybe add enough batteries to give you 10 to 15 minutes of power after gen stops. could a turbine be made efficient enough to use in this situation?

 

[737steve]

Interesting thought. Have a gas turbine that runs at a constant speed chosen for efficiency, feeding an electric powertrain. Your throttle could be a variable frequency drive. Reverse thrust with no hydraulics! There would be a crowd around it at Oshkosh.

 

[tspear]

serial hybrid would be nice. maybe add enough batteries to give you 10 to 15 minutes of power after gen stops. could a turbine be made efficient enough to use in this situation?

Short version; it depends. And I am going on memory from reading what engineers and others have calculated....
If you run ROP, switching to a small turbine will not have significant impact on the utility of your plane. Here are some rough numbers:
1. Traditional single stage turbines will typically be between 0.8 and 1.2 BSFC; some of the better ones getting down 0.7
2. New regenerative small turbines, like TurboTech, appear at this point to be closer to 0.50 - 0.6
3. ROP: around 200 degrees used at takeoff for many engines is closer to 0.8. In cruise often closer 100 degrees ROP, close 0.6 BSFC.
4. LOP: around 50 degrees (cruise below ~65% power), is closer to ~0.40 BSFC.

So, basically if you run ROP and get a regenerative turbine you will likely be around the same utility. Excluding STC costs, my guess payback is measured in thousands of hours.

Note: regenerative turbine technology has existed for many decades. However, they have always been practical issues with it, that TurboTech has claimed to fix. I know of a couple other forms attempting to also build regenerative turbines and making the same claims, but none have released a product yet.

Tim

 

[cowman]

If we're talking about complete powerplant replacements I think Jet-A/Diesel is clearly the best and most viable choice. Of course they're heavier and probably need new airframes designed around them rather than being a realistic retrofit for existing avgas burners. If you could build and sell an airplane for the kinds of prices people saw back in the 60's that would be great. However, you can't so we run into the problem of who is going to buy a multi-million$ piston single?

Propane has less energy density than gas by a significant margin and it will not produce as much power. The fuel weighs less but you need heavier tanks.... I don't really see how you could get around those issues.

Electric aircraft have been tried, the batteries are just too heavy for the amount of energy stored. From what I saw nobody could figure out how to build one that would work with enough range/endurance to do anything useful. IDK about a turbine-electric hybrid but I suspect you'd run into a simmilar weight issue with all the extra hardware and fuel you'd have to carry for it to work.

Gas has been king for a long time for a reason. Really for pilots who only want to bomb around their local area by themselves and make the occasional $100 hamburger run, experementals/EABs running mogas are already there and they're the fastest growing part of GA. I'd move that way myself but I don't know of any that can match my Lance in terms of people/baggage carried at speeds suitable for long distance trips.

 

[Racerx]

Hence, if installing a Surefly electronic mag I would disable the timing advance if I had a turbo.

Per surefly,

To operate the SIM in variable timing mode, the engine onto which the SIM is installed must comply with the following requirements:
1. Normally aspirated,
2. Have Cylinder Head Temperature (CHT) monitoring capability,
3. Use minimum of 100-octane low lead aviation fuel.

 

[MackMooney]

I'd really like a diesel but unfortunately, unless diamond starts selling theirs it'll PROBABLY never happen. diamond just upped their gross weight when they added the diesel. GM turbodiesel on my mooney would be nice. hmm, maybe even a turbodiesel serial-hybrid 8) jk

 

[cowman]

I'd really like a diesel but unfortunately, unless diamond starts selling theirs it'll PROBABLY never happen. diamond just upped their gross weight when they added the diesel. GM turbodiesel on my mooney would be nice. hmm, maybe even a turbodiesel serial-hybrid 8) jk

I'm patiently waiting for decent DA-62s to depreciate into the low 6-figure price range. You know... if I'm still in good enough health to fly if/when that ever happens.

 

[455 Bravo Uniform]

@Gary Ward I seem to recall a propane powered drag car that ran around NE Ohio (Quaker?). Had you ever seen it? Google search didn’t help. I think it was blue, maybe a Monza or other small coupe. Pro Pain or something like that, unless I’m mixing up multiple 40 year old memories to create this one, lol.

 

[MackMooney]

I'm patiently waiting for decent DA-62s to depreciate into the low 6-figure price range. You know... if I'm still in good enough health to fly if/when that ever happens.

Wife should be scared if i EVER get enough cash for DA-62, i'd think about moving out of the house and sleeping at the plane.

 

[tspear]

I'd really like a diesel but unfortunately, unless diamond starts selling theirs it'll PROBABLY never happen. diamond just upped their gross weight when they added the diesel. GM turbodiesel on my mooney would be nice. hmm, maybe even a turbodiesel serial-hybrid 8) jk

Austro (the Diamond company that makes the engines) is willing to sell the engines; at least a few years ago. It was to OEM only and need a firm commitment order; but they would not say what the order size was. What was interesting (at least to me), the sales rep specifically stated they would be willing to work with any OEM that sells at least 25 planes a year, for example Vans.

DeltaHawk has also been certified. And they have a few planes flying now, for example:
1. The RV-14 v1 is almost finished with v2 already under construction;
2. Piper Seminole DX is going through test flights. One pundit said it looks like Piper is going the STC route, so open question if Piper will only use it for new planes or retrofits.

Tim

 

[pfarber]

Unless leaded fuel is outlawed, why would an FBO spend any money to change to unleaded?

Because the FAA treats GA like trash. The FAA should raise registration costs from $5 to $100 and use that money to subsidize MOGAS or unleaded fuel depot installations at GA airports (not class Bs). Also AVGAS is taxd at about $0.20/gal. That tax should also go (a % thereof) subsidizing MOGAS/unleaded fuel stations. The switch to unleaded should be the #1 priority of the FAA so the kinks can get ironed out. But most likely its gonna take ANOTHER 20 years until its complete.

60-80% of all GA piston AC can run MOGAS. Yet MOGAS is only installed at about 3% of airports.

The unleaded fuel 'issue' has been largely been mismanaged by the government.

ADS-B compliance took less than 10 years. Its been 20+ years and still no widespread unleaded fuel available. And now we're gonna have to wait for the local govt's (who operate the local airports) to put up money to switch from 100LL.

 

[tspear]

I'm patiently waiting for decent DA-62s to depreciate into the low 6-figure price range. You know... if I'm still in good enough health to fly if/when that ever happens.

By then, they will be VFR only because the avionics are so out of date and cannot be upgraded.

Tim

 

[Racerx]

@Gary Ward I seem to recall a propane powered drag car that ran around NE Ohio (Quaker?). Had you ever seen it? Google search didn’t help. I think it was blue, maybe a Monza or other small coupe. Pro Pain or something like that, unless I’m mixing up multiple 40 year old memories to create this one, lol.

Roush brought it back.

Passion. Power. Propane. - ROUSH CleanTech

Passion. Power. Propane. Susan Roush-McClenaghan is breaking barriers and paving the way for women in motorsports. In 2009, Susan Roush-McClenaghan became the first woman to win in the special final...

roushcleantech.com

 

[455 Bravo Uniform]

Roush brought it back.

Passion. Power. Propane. - ROUSH CleanTech

Passion. Power. Propane. Susan Roush-McClenaghan is breaking barriers and paving the way for women in motorsports. In 2009, Susan Roush-McClenaghan became the first woman to win in the special final...

roushcleantech.com

I’m wondering if that’s the same team? I remember 1980s-1990s…

 

[WDD]

Hank Hill approves

 

[Half Fast]

Just musing.......

Back in 2021, Textron released a service bulletin, SEB-28-04, which approved UL94 (and a few other fuels) for a variety of Cessna and Beechcraft planes. It simply required the installation of new fuel placards, plus a flight manual supplement for planes having an AFM, and thus bypassed the need for the Swift STC. I wonder whether Textron will revise the bulletin to include 100R.

Even that might not be necessary, as Textron stated "minimum grade," so presumably if they've approved the planes for 94, then 100 should also be acceptable.

 

[172andyou]

Because the FAA treats GA like trash.

10% or so of airports have commercial service. Despite this, the US has the best GA system in the world.

The FAA should raise registration costs from $5 to $100 and use that money to subsidize MOGAS or unleaded fuel depot installations at GA airports (not class Bs).

There are 5000 airports with fuel. You're gonna need a lot more than the $5m a year this scheme would raise to get mogas into them.