📌No cheats, glitches, exploits, infinity, modifications or slipping clutch exploit, clutches must be at 1. XML editing is allowed for decorative purposes but pay attention to drag-glitch which is not allowed. To find if any part of your vehicle is drag-glitched which occurs when there is a gap in the body, simply place a fluid meter on its exterior and spawn it on ground (not water). If fluid meter shows positive value, then it is glitched, connect the parts of your vehicle to fill the gaps. There can be minor exceptions like wheels or small decorations.
📌It will be land based aircraft, not seaplane or amphibian.
📌Engine is modular, having 1, 2 or 3 small cylinders, naturally aspirated, without flywheel.
📌There can be auxiliary engine on the aircraft (to generate electric for example) but it cannot be providing power to the propulsion (propellers) system. This way twin-engined aircraft with an additional auxiliary engine will still be considered as twin-engined aircraft but auxiliary engine will still get weight blocks for cylinders, radiator and its fuel.
📌Maximum one propeller per engine
📌Min range is 50km, min endurance is 15 min for any aircraft.
📌Each crew member and passenger will have a seat, any seat type (or bed) is ok.

💼Minimum passenger number for AIRLINERS:

1 for single engined aircraft.
4 for twin engined aircraft.
6 for three engined aircraft.
10 for four or more engined aircraft.

👨‍✈️Minimum crew is 1 but increases if it is an AIRLINER:

+1 as co-pilot if endurance is greater than 120 minutes in cruise,
+1 as engineer if there are 4 or more engines,
+1 as navigator/radio operator if range is greater than 900 km,
+1 as steward if there are more than 10 passengers. Plus +1 per 50 passengers. (e.g: 3 stewards for 120 passengers),
+3 as backup crew if endurance is greater than 360 minutes.

👨‍🚀Minimum crew is 1 but increases if it is a RECORD BREAKING AIRCRAFT:

+1 as co-pilot if endurance is greater than 360 minutes in cruise,
+1 as engineer if there are 4 or more engines,
+1 as navigator/radio operator if range is greater than 1500 km.

If your aircraft is an airliner, it will be valid for flight records as well, because required crew number encompass this.

🔷Weight blocks to be added:

+10 per (small) cylinder
+9 per 3x3 radiator, +25 per 5x5 radiator, +15 per 3x5 heat sink (coolant water in radiators)
+0.064 per liter of diesel for custom tanks (1 liter of diesel as 0.84kg)
+0.074 per liter of diesel for prefab tanks (1 liter of diesel as 0.84kg)
+10 per seat/bed (70kg average person weight and 30kg luggage)

You may add battle cannon barrel (40 mass) in place of 4 weight blocks if you want. Tajin's Stormworks Toolbox ( https://rising.at/Stormworks/stats.php ) is useful to see how many blocks of certain type even if they are hidden by XML.

Because this competition is about airliners and record breaking aircrafts, realistic weight of other elements such as weapons are out of scope.