In theory 2 stroke engine is twice as good as 4 stroke engine. In practice 4 stroke engine is usually better. 4 stroke engine beats 2 stroker in gas exchange.

2 stroke engine does not need valves. It is good for high rpm engines. Like an engine for small motorbike. Common valve system limits 4 stroke rpm to around 6 000 rpm. 2 stroke engine does not flywheel either. It is quite a lot lighter than 4 stroke engine.

Usage of high rpm almost always results to poor fuel efficiency. Regardless of the engine type.

You can add a second chamber to 2 stroker. It would have straight sealed rod in new chamber, which is between fire chamber and crank system. You can shape the 2nd chamber for optimum gas exchange.  It would improve gas exchange, make 2 stroker much more competitive against 4 stroker. Lubrication is a small problem with two chambers. Piston needs rings at both ends. Rod has to be hollow for feeding oil into piston's movement area. Another way for the lubrication are holes in the block. In overall engine would be higher than now, but fully functional. Better than current two stroke engine.

- - Car batteries - -

What makes charging dangerous ?
When you charge electro-chemical battery, you enrich O₂ into O₃. Ozone creation makes the charging dangerous. Ozone burns things more efficiently than oxygen O₂. According to books, ozone is born, when ultraviolet light or electric radiation gets in touch with oxygen. During sunny day ultraviolet light exists in everywhere, but this ultraviolet does not convert oxygen to ozone.

In electric wires, conductor material reacts with oxygen, before it reacts with electricity. Radio waves are not known to react with oxygen.

Ozone itself does not make charging dangerous. Explosion in charging room needs hydrogen or free coal atoms in the air. In charging third O atom obviously comes from water-acid liquid/gel, which is inside the battery. From the liquid, water vanishes and acid stays.

- Internal gas creation belongs to charging. Without small ventilation holes, battery is in danger to explode, when you charge it.
- Electro chemical process is a physical process, in process electrons moves from one place / plate to another.
- In electro magnetic process you create static electric tensions into material, usually you rotate particles.

14th January 2019 - Boat : Double Propel

I was asked ( probably once again ), what is the meaning of double propel. Double propel pre-accelerates water / air. It sort of allows you to lengthen the distance, where you accelerate liquid / gas. Double propel reduces turbulence, resistance and leaks from the wings.

In principle new fully covered propel should be capable of giving almost jet like thrust to plane. Have a hunch that boats would already use fully covered propels.

Possible that the hunch comes from the photos. A tilted-angle photo from the typical boat propeller in the picture, makes the propeller look like, that the wings has 100% or ever bigger coverage.

I was asked about cars with voice control. Voice control is doomed thing. You can never control unintentional voice commands.
Voice control tech is over 20 years old already. When you are for example in rushed railway station and someone shouts your first name.
Almost everyone, who shares your first name, reacts to the call. When humans make mistakes, manmade things makes more. It is the general
rule for all AI ( artificial intelligence ) systems.

Talking real-life cars are also around 20 years old. People didn't like them. They vanished from the markets very quickly.

Smart cruise control is system, which keeps the distance to car, which drives before you. System is developed for copter car. In copter car the same transmitter - receiver system acts as private air control system. Copter car can have "invisible" incoming vehicles from 3 directions. From back, above and below. You need help for checking, that all directions are clear. 

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If you are not familiar with west European car market, in west Europe rear driven cars dominates executive-full sized markets. BMW and Mercedes are popular in large family car class.

Next generation Caprice is a response to request to get the traditional full sized American car back. V8 pressure sensor engine, hydraulic suspension and butterfly doors will bring quite a lot of new to old concept.

In second hand car markets Ford Mustang with V8 engine costs twice as much as with V6 or I6. In critical situations stiff rear axle is at least as safe as independent. Stiff axle is demand for soft. comfortable suspension. Lengthwise control bars in the front are also good for softer suspension. With upper and lower gas springs, you can adjust stiffness independently from ground clearance.

Both GM and Ford gave up from development of traditional full sized cars. Caprice-Impala and Crown Victoria fell behind the other cars. They concentrated on SUVs, the last major buyers of traditional full sized cars were cab companies and cops. Neither one buys Sport Utility Cars.

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In principle it is possible to build HT body, without full height B-pillars. So, that the whole side window area is open. Butterfly rear door has usually hinges in the back. Rear hinges in the front makes it difficult to build a system, where you can open front and rear doors at the same time. Then the fully opened rear door tends to hinder entrance to front seats. You can compensate the lack of B-pillar with roof's beam-strength system.

Body without B-pillar is also possible. When so, front and rear doors locks to each other. Closed doors forms attached beam system.

Butterfly doors have been a standard for Lamborghini's middle-engine dream car models.

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Butterfly door has the same than copter car. 2.5 meters is the maximum height during opening. It is height of private garage in newer detached house. Caprice is around 2 meters wide. In order to open doors from both at the same time, it needs 5 meter free width.

In order to improve turning and parking of a big car, it is possible to use turning rear wheels. Full time 4 wheel steering is tricky, might want to limit rear wheel steering to parking : big steering angle in low speed turns. After front wheels are near the maximum, rear wheels start to turn. In 1980s Mazda had full time 4 wheel steering in common sedans, it was removed after few years. Without big sensations.

With the butterfly doors and parking aids traditional full sized suits also to European and Asian streets / roads.

9th May 2019 - Correction to 4 wheel steering

When you build 4 wheel steering so, that at certain steering angle rear wheels start smoothly to assist front wheels, the system can be a mechanical full time system. In for example high speed rear wheel slide, the turned rear wheels pushes the rear away from the slide. Mechanical system keeps the steering logics. So that driver always knows how car goes with certain steering angle. You can also practice high speed slides and other difficult situations.

If you make the smoothness and rear-wheel steering with electricity, you should use fixed system in the addition of rear wheel assistance. 
Idea that you could beat driver with sensors and electrically steered rear-wheels works in tv and ads, but not in real life situations.

10th May 2019 - New Full Sized car

You cannot build voice controlled cars, but you can use voice alerts into cars.
In vehicles voice alert is better than visual alert. Visual alert needs that you focus your eyes into alerting light, gauge or display. Voice alert comes to your ears, right after the alerted thing takes place.

The new GPS with safety checks from incoming cars, cyclist and pedestrians would need voice alerts. New parking aid for full-sized car checks distances from each side and corner. With 5 to 10 cm or 2 to 4 inch accuracy. This system is another thing, where voice alerts are very good.

Voice alerts must have options with selections for alerts, which comes out with voice. Then you must be capable of easily muting the currently active voice alert.

Here is the new full sized American car, a car Americans would love to buy. All Donald has to do, is to keep his promises, and give Americans enough work and money for buying these awesome new cars.
Did my best in order to get the best existing and new things into concept. Parking aid and small turning radius makes concept suitable for Europeans and Asians, too. Traditional full sized US car was too big and clumsy for European park houses and places. On the streets and roads Caprice fits and goes well.

How much car costs ?
More than current small full-sized car. Not necessarily much. Bigger car needs more steel, wires, cloths and plastics. Design costs goes down with mass-production. Total design costs of for example next generation Toyota Corolla are bigger than new airliner's or fighters design costs. Design cost for one new Corolla is much more smaller than planes. When so, copter cars give many new things to aviation.

Basic body will be hard top, without B-pillar. When you open both doors, the whole passenger department opens.
At the floor level there is a small bump for locks and for sealing the closed doors together. Possible that there will be doors and hinge systems, which opens both vertically and horizontally.

Top speed ?
If you raise highway speed limits to 160 km/h / 100 mph, top speeds could raise to 240 km/h or 150 mph.

How does Caprice differ from Rolls Royce ?
Interior is made from fabrics and plastics. Mine has optional leather seats. Caprice is made for family. Front doors are big, rear doors are small. Same goes to space division. Space weighs to front seats. Rolls is made for driver and passengers at the rear seat. Interior has expensive materials, polished wood, best quality leather and so on.

- - Safety system - -

What kind of the thing safety system's transmitter-receiver is ?
It is an electric reflector. It costs slightly more than optical reflector. Electric reflector can have classes. Trucks and private cars can be separated. Fire trucks, ambulances and cop cars can have an alert class reflectors. Trains and trams can have their own classes, trains stronger transmitters. Then there can be classes for bikers, pedestrians and young kids. When there is kid somewhere the car, the new GPS gives you a kid alert. Young kids are not yet fully familiar with traffic rules, they always need additional attention.
Animals and pets can also have their own classes and electric reflectors.
Why not.  You use electric reflector much like optical. When go for a walk, you put and carry the small gadget in your pocket. Vehicles have mounted optical reflectors, electric reflectors are also mounted. Classes are the most accurate private things, the general usage electric reflector can legally have.

Safety system and electric reflectors converts many traffic regulations into recommendations.
It reduces also need to control traffic violations.

Is safety system too good to be true ?
No. It is one way to take advantage from computers. System needs CPU power, there can be thousands of transmitters in the area. Programs for new GPS are not simple and easy. Then the system increases electric radiation. Carbon-hydrogen body is almost immune to minor electric radiation. On the other hand, the new network tech reduces aired electric radiation.

If you bend tips of the plane's wings, upwards or downwards ?
Downwards. Reason is very simple. Downward bend prevents pressure leaks from the below, boosts the leaks from the above. Correct tilt direction is an old thing. It belongs to the very basics of the plane design. Upward tilt reverses everything, it boosts the fall from the clouds. Upward tilt increases fuel consumption, makes lift-offs more difficult and so on.. Flat floor body has always hole in the center of bottom, walls at the sides. System doesn't affect to plane's co-efficient factor. The increase in co-efficiency is rough match to increase in lift.

Plane has horizontal and vertical aerodynamics. Horizontal is unwanted thing, that results to air resistance. Vertical co-efficiency is wanted thing, it keeps the plane in the air.

How do you build water booster to lift offs ?
You have water tanks in wings. You fill them at airport, use the water during lift off. Fly with empty water tanks.