YES ! …. for understanding aerodynamic lift, wind tunnels are the wrong tool. The same applies to CFD (computational fluid dynamics) simulations, as well. The video below shows the famous Howard Hughes’ Spruce Goose H-4, attempting to takeoff on its maiden flight. It is a glittering example of the necessity of reaching a certain critical speed V1 before the wings generate enough lift to get airborne. You can witness how even its 8 engines, blowing air over the wings at full power like in a wind tunnel, could not create lift. Lift was available only when the aircraft reached V1 of 95kts. That is why no wind tunnel is capable of producing aerodynamic lift, no matter how fast air is blowing in it over a test wing. This fundamental handicap renders the wind tunnels unable to produce correct airfoil performance data. The only way any upwards reaction force similar to lift can be produced in a wind tunnel is by tilting the wing upwards. This introduces an angle of attack which is not required for the aerodynamic lift generation by the airfoil. Due to this major drawback the wind tunnels are the wrong tool for lift experiments. Note the narrator calling out the airspeed until rotation at 95kts, i.e. V1 for that plane.

The Zone Theory clearly states that the airfoil can only produce lift exceeding MTOW when it has reached a certain critical value called V1. It is the point where the vacuum in the Induction Zone is sufficient to create lift.

Lift has many forms, and given enough power anything can be made to fly, be it a mosquito or a moon rocket. Same applies to the inverted flight of aerobatic stunt planes or the notorious F-104 Starfighter (the widow maker), both relying on angle of attack Newton reaction lift. Both these types use non-conventional wing cross-sections, and require enormous amounts of fuel to remain airborne. Similarly, objects can be made to show tendency to “fly” in wind tunnels or CFD simulations, but that is NOT the lift force that runs the global air transport industry.

What we are solely interested in, is the vacuum lift force generated by the bird derived asymmetrical airfoil, discovered by the Wright Bros., almost 100-years ago. This and only this type of airfoil is capable of generating lift in the most energy efficient manner, with utmost inflight stability, and safety. No other form of wing is capable of all these features and is the only design used in Aviation. The Zone-Theory is THE only theory which demystified the secret of this lift, and many other related physical phenomena, such as thermodynamics and other flight characteristics.

Failure of wing design based on Bernoulli has already been proven by Einstein in the following video: https://youtu.be/g0xa4UvucA4?si=9saqzNE-HwLb9FAZ, which you all may have seen already. This should clear a lot of ambiguity from the content of Zone Theory, and why wind tunnels are wrong about understanding airfoil behaviour in the real atmosphere.

Similarly, we can observe the necessity to achieve V1 or takeoff speed in the bird kingdom where large birds just simply can’t leave ground by flapping wings alone. They have to run like an aircraft before their airfoil generate enough upwards lift to carry them up. Watch here.