# Airplane for the Common Denominator

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#### cluttonfred

##### Well-Known Member
Supporting Member
The problem with this thread, and I have made this mistake myself, is that we keep getting away from the OP's intent. Yes, we can debate what would be the criteria for the most universally-accepted plane, or how to define the "common denominator" potential homebuilt aircraft builder in terms of finances, skills, workshop space, time, etc. That wasn't the question. The OP defined the mission this way (I have added numbers to the points):

1. Comfortably seat one pilot
2. Travel faster than driving
3. Use a common enough reliable engine that’s mogas-friendly and not a never ending science experiment
4. Be easy enough to fly, capable of straight-forward pilot transition from a common type
5. Be resilient enough to survive outside tie down in any US state without needing major refurbishment
6. Designed for scratch building using common tools and ordinary raw materials and hardware

Going point by point, a few notes....
1. Sounds like a single-seater is sufficient but does not excluded a two-seater, anything larger would seem inefficient for the mission.
2. That speed requirement would seem to exclude Part 103 or anything else very slow. With highway speed limits at 75 mph in much of the USA, I'd say a cruising speed of 100 mph or more would make sense.
3. Mogas-friendly, common, reliable to me means a modest LyCon, a VW, a Rotax 4-stroke, or an established small auto engine conversion.
4. Ease of piloting is very subjective, but the transition from a common type means no Flying Fleas or other outliers, normal three-axis control, tricycle or taildragger, and reasonably docile handling.
5. Most people interpreted the outdoor tie-down requirement as favoring all-metal construction, though I think there is a case for mixed tube-fabric construction as well. Personally I would exclude wood and composites though some may argue otherwise.
6. The scratch building and common materials means a plans-built design.
What does that leave us?
• Any Sonerai (if you accept a fabric-covered tube fuselage and tails)
• Any scratch-built Sonex
• Davis DA-2A
• Aerosport Quail
• Any Thatcher
• Any scratch-build Zenair/Zenith
• Thorp T-18
• Midget Mustang/Mustang II
I am sure there are more and there are also some modest kit-only designs (RANS, Sky Ranger, etc.) that might fit the bill.

#### Tom DM

##### Well-Known Member
Supporting Member
snip

Going point by point, a few notes....
1. Sounds like a single-seater is sufficient but does not excluded a two-seater, anything larger would seem inefficient for the mission.
2. That speed requirement would seem to exclude Part 103 or anything else very slow. With highway speed limits at 75 mph in much of the USA, I'd say a cruising speed of 100 mph or more would make sense.
3. Mogas-friendly, common, reliable to me means a modest LyCon, a VW, a Rotax 4-stroke, or an established small auto engine conversion.
4. Ease of piloting is very subjective, but the transition from a common type means no Flying Fleas or other outliers, normal three-axis control, tricycle or taildragger, and reasonably docile handling.
5. Most people interpreted the outdoor tie-down requirement as favoring all-metal construction, though I think there is a case for mixed tube-fabric construction as well. Personally I would exclude wood and composites though some may argue otherwise.
6. The scratch building and common materials means a plans-built design.
What does that leave us?
• snip
I am sure there are more and there are also some modest kit-only designs (RANS, Sky Ranger, etc.) that might fit the bill.

There are none. In order to beat a car in any mission < 200 NM the craft must allow operation "without airfield" or "off airfield " (preferred more than once ), be able to land safely in tighter spots like a back-garden etc.

This non-existant airplane: single -seater , VTOL preferred with automated take-off/landing or even flying, IMC, overall dimensions max 6x6 m, range 300 NM, cruise 100 Kts, , safe (allowed over urban areas) and semi-silent (noise level car like)

The closest existing thing appears to be some gyrocopter or a single seat experimental helicopter. There might be objections regarding the spinning rotorblades if you hop in it to for the supermarket-run. In some "open space"-countries a STOL-airplane may fit.

However all those people carrying drones, annonced last year for 6 months ago, seem to suit just fine.

#### cluttonfred

##### Well-Known Member
Supporting Member
Point of order...for "travel faster than driving" I took that to mean between one small airport and another. In other words, as I fly over the cars on the highway do I feel like I am making better time than they are. If the issue is practical commuting or cross-country travel, that's an entirely different conversation.

##### Well-Known Member
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The Rutan canards seem to qualify.

BJC
Can't be stored outside.

Excluding #6 makes it the RV. I think that the Thorp and Mustang violate #4.

#### Tom DM

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Supporting Member
Point of order...for "travel faster than driving" I took that to mean between one small airport and another. In other words, as I fly over the cars on the highway do I feel like I am making better time than they are. If the issue is practical commuting or cross-country travel, that's an entirely different conversation.

Recreational pilots fly from airport to airport as our "mission" is the 100 $hamburger, the 75$ coffee etc. After landing most do not even leave the airfield.

However ever non-pilot flies for home to destination. He /she is landed comfortably landed at an aerodrome and can than carry the 2-4 bags to a taxi, conveniently waiting at the airstrip and then be driven to the hotel, apartments etc.

So a car will not beat the plane for a pilot on his hamburger-mission but for most others it will.

#### Vigilant1

##### Well-Known Member
Supporting Member
All are invited to Be: as of tomorrow Premium Mogas will be at 2.4 Eur /l (that is more than 10 US$per Gallon) How much of that 2.4 euro/l is the underlying cost of the product and how much is tarrifs and VAT? The "current situation" is obviously driving up the cost of petroleum products, but in "normal times" (May 2020) the pump price in Belgium was 1.15 euro per liter and 80 cents of that was VAT + tarrifs. Technically, at least in normal times, fuel isn't expensive in Europe. The taxes on auto fuel are expensive. Same with 100LL? Prices for mogas in various EU countries:https://i0.wp.com/www.fuelseurope.eu/wp-content/uploads/Chart-04-SR2020-FuelsEurope.jpg?resize=1024,1024&ssl=1 #### Tom DM ##### Well-Known Member Supporting Member How much of that 2.4 euro/l is the underlying cost of the product and how much is tarrifs and VAT? The "current situation" is obviously driving up the cost of petroleum products, but in "normal times" (May 2020) the pump price in Belgium was 1.15 euro per liter and 80 cents of that was VAT + tarrifs. Technically, at least in normal times, fuel isn't expensive in Europe. The taxes on auto fuel are expensive. Same with 100LL? Prices for mogas in various EU countries:https://i0.wp.com/www.fuelseurope.eu/wp-content/uploads/Chart-04-SR2020-FuelsEurope.jpg?resize=1024,1024&ssl=1 Fuel (ex-factory) in Europe is not a dime more expensive as in the US or elsewhere. Your assumption - taxes and taxes on taxes- does indeed complete the picture. Belgium applies the "cliquet"-system: if the price of fuel rises, the absolute amount of taxes (which are percentages ) rise along. However if the price of the oil becomes less (marketreasons, overproduction etc etc), the reduction is divised in two: one halve reduces the end-user price, the other half is added to taxes. As such the percentage of taxes compared the ex-factore-price also always grows. AvGas is worse: it carries an extra "lead"-taxe, specifically created for the high lead levels of 100 Low Lead There is this saying: if you don't smoke, if you don't drink and if you don't drive a car, than you are a tax-evader. On tabacco-products , alcohol and fuel taxes represent 70-85% of the end-user price and a very sizeable income to the government (which is known to hate competition) For the moment there is "fuel"-tourism: in the Netherlands fuel is even more expensif than in Belgium/ Germany. Now some Dutch have been caugt hauling fuel in jerry-cans from Germany. Apparantely one can legally transport 240 l ( 63 US Gallons) in jerrycans in his car. This loophole will be rapidely closed ... for evident safety reasons no doubt. #### Vigilant1 ##### Well-Known Member Supporting Member Belgium applies the "cliquet"-system: if the price of fuel rises, the absolute amount of taxes (which are percentages ) rise along. However if the price of the oil becomes less (marketreasons, overproduction etc etc), the reduction is divised in two: one halve reduces the end-user price, the other half is added to taxes. As such the percentage of taxes compared the ex-factore-price also always grows. Wow, an inexorable, automatic ratcheting tax rate increase. No new rules/votes needed, price volatility does the work. Diabolical, and politically ingenious ("When oil prices went up, motorists got used to the higher pump prices and were willing to pay them, apparently. There won't be outrage when oil prices go down since the pump price is going down, too (a little). Sure, the tax rate went up and will now stay up forever, but you are paying less right now, aren't you?? Don't be greedy! "). Let's talk no more of it. There's no reason to give anyone in the US another "bright idea." Last edited: #### Vigilant1 ##### Well-Known Member Supporting Member AvGas is worse: it carries an extra "lead"-taxe, specifically created for the high lead levels of 100 Low Lead Well, that's great news! That tax will surely go away when zero lead avgas becomes available. #### Toobuilder ##### Well-Known Member Supporting Member Recreational pilots fly from airport to airport as our "mission" is the 100$ hamburger, the 75\$ coffee etc. After landing most do not even leave the airfield.

However ever non-pilot flies for home to destination. He /she is landed comfortably landed at an aerodrome and can than carry the 2-4 bags to a taxi, conveniently waiting at the airstrip and then be driven to the hotel, apartments etc.

So a car will not beat the plane for a pilot on his hamburger-mission but for most others it will.

Every time I hear things like this I am reminded of the saying that "...those that say it cant be done should get out of the way of those that are already doing it..."

And then I remember you are from Europe.

Bottom line is that I, and my circle of friends use our airplanes for basic, errand type transportation quite often. And the so called "last mile" that people struggle with is really not hard at all. There are countless options to get around once you land. Rideshare, taxis, courtesy cars, shuttles, car rentals, FBO shuttles, bicycles, feet, friends.... Not hard most of the time.

#### Tom DM

##### Well-Known Member
Supporting Member
Well, that's great news! That tax will surely go away when zero lead avgas becomes available.

We have zero lead avgas, UL 91

The number of taxes that went away, I can count with fingers on 1 hand having reserve.

The UL91 carries the same "lead-taxe" as AvGas 100ll or better said a similar (as identical) percentage,
Expleaning Accijnzen which are taxes on which taxes can be applied, would take us to far out the scope of homebuilt aircraft.

#### Tiger Tim

##### Well-Known Member
For the moment there is "fuel"-tourism: in the Netherlands fuel is even more expensif than in Belgium/ Germany.
About twelve years ago I used to routinely drive into the US for fuel. I lived in a border town and given the difference in price it made a lot of sense. Typically some friends and I would meet up once a week or so for dinner at an American restaurant and we’d all gas up on our way home. Some had trunks full of jerry cans but I never bothered.

#### Tom DM

##### Well-Known Member
Supporting Member
Every time I hear things like this I am reminded of the saying that "...those that say it cant be done should get out of the way of those that are already doing it..."

snip

Bottom line is that I, and my circle of friends use our airplanes for basic, errand type transportation quite often. And the so called "last mile" that people struggle with is really not hard at all. There are countless options to get around once you land. Rideshare, taxis, courtesy cars, shuttles, car rentals, FBO shuttles, bicycles, feet, friends.... Not hard most of the time.

I completely agree but then I am used to compare appels to appels. My Thorp is not Harmon Rocket but I know for certain that I cannot outrun a car on a 200 NM stretch *unless* there is something heavily in favor or against.
It is not only linked to the fysical car / airplane but also quite heavily influenced by restricted airspaces

#### Tiger Tim

##### Well-Known Member
What kind of Thorp do you have that can’t keep up with a car over 200nm? I guess alternatively what on earth are you driving?

#### Tom DM

##### Well-Known Member
Supporting Member
About twelve years ago I used to routinely drive into the US for fuel. I lived in a border town and given the difference in price it made a lot of sense. Typically some friends and I would meet up once a week or so for dinner at an American restaurant and we’d all gas up on our way home. Some had trunks full of jerry cans but I never bothered.

We have that very extensively in the South of Belgium as there is an even smaller country, Luxemburg , which is most literally a tax haven.

It has even existed with airplanes which hopped to and from France: there was a modified Stelio Frati at Grimbergen which was used in a race Brussels -Tokio. The plane had close to 120 USGallons extended range tanks.

Several trips a day to and from but it did not take long for Customs figure it out.

#### Toobuilder

##### Well-Known Member
Supporting Member
I completely agree but then I am used to compare appels to appels. My Thorp is not Harmon Rocket but I know for certain that I cannot outrun a car on a 200 NM stretch *unless* there is something heavily in favor or against.
It is not only linked to the fysical car / airplane but also quite heavily influenced by restricted airspaces

I can give you a real world example: Aircraft Spruce is 68NM from my home. The drive there and back is probably a 7 hour ordeal even in "good" LA basin traffic. My neighbor uses his RV-6 as a weekly shuttle to go grab all our orders, and he can be out and back in a little over an hour.

#### Tom DM

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Supporting Member
What kind of Thorp do you have that can’t keep up with a car over 200nm? I guess alternatively what on earth are you driving?

I fly T211s which all cruise around 90-100 Kts. The cars are "normal" and allow average speed between 140-160 kph. I have some quite faster but even in Germany it become close to impossible to average speeds around or slightely above 200 kph. Fastest average speed in a car: 235 kph over 880 km... and it was a diesel.

The major loss of time for a small airplane to a car (in Western Europ) comes from airspace restrictions.

I withnessed stupidy: Roeselare (Belgium) to Kerpen (Germany) sunday morning 06Hr00 open road: 300 km one way. 1 Hr 10 minutes in Ferrari Testarossa. Owner shook off Police Helicopter... once.

I presumed such to be impossible anymore but sometimes opportunities arise: Cannonballers were not to only to take advantage of Covid-free streets 2 years back. Boys will be boys, stupid is stupid but there is what we call "Het Groot Gelijk" (translated "Knowing Best"). The Roeselare-Kerpen-record stands now a 55 minutes in an Audi RS6. With the T211 I would flightplan it at 1Hr45.

#### Tom DM

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Supporting Member
I can give you a real world example: Aircraft Spruce is 68NM from my home. The drive there and back is probably a 7 hour ordeal even in "good" LA basin traffic. My neighbor uses his RV-6 as a weekly shuttle to go grab all our orders, and he can be out and back in a little over an hour.

Real world examples can prove anything as they are linked to specific situations.

An example: I take off at Calais to land Lydd Airport 30 minutes later. It is but 25 NM. A car will need a minimum of 3 hours , you may choose any car (as long it does not fly). There is this small thing called the English Channel.

So is this specific situation proof that a plane is faster?

As to the RV-6 Jockey: he pops to Aircraft Spruce to pick up the 500 kg lathe you ordered. Sure he will be back in an hour.

#### Toobuilder

##### Well-Known Member
Supporting Member
Real world examples are the reason I continue to do things you apparently can't even imagine. Not your fault - I spent a couple of weeks with test pilot students from all over the globe recently and they couldn't believe it either... Even after I showed them exactly how I did it.

Things are different here.