Here are the fifteen revolutionary advantages of horizontally oriented Transformer Wings
followed by the fifteen disadvantages of traditonally, vertically oriented Sails/Wings:
1. Maximum Wind Speed Access
Horizontal wings encounter highest apparent wind speed (AWS) precisely at TWA=0 degrees exactly when vertical sails become useless.
Additional notes:
A traditional tacking sailboat have 30-41% more distance to sail to reach upwind destination while while at the same time experience lower AWS as there is a trigonometry involved.
In addition when sailing toward the wind at TWA= 0 degrees the boat is
not exposing the hull side to wind but have the lowest drag possible.
as showed on Fig 12 in the book. This way the whole vehicle drag is at its minimum
also the air flow around the boat is not disturb as much as for tacking boat.
Still we can see another advantage of this higher AWS and that is that the horizontal TW orientation enable to lift the whole boat also at very low TWS as the boat speed adds to the TWS increasing very quickly the lifting force and produced power.
2. Fresh Airstream Advantage
Wings move across the airflow rather than through it, always encountering undisturbed air instead of their own turbulent wake.
Additional notes:
This is a argument that is difficult to quantify but it have a positive rather than negative impact on TW performance.
In the book it is mentioned the Betz limit.
I am also sceptical about the Betz limit as it do not apply for the TWs
in the same way it affects wind turbines.
This is a way that I try to say for the reader that Wind Turbines do not compete with AquaFlyer and AquaFlyer is not replacement for Wind Turbines as it is superior due to fact that is moving while Wind Turbines are stationary and just stands still waiting for any breeeze to show and often below 10m/s... but my goal here is that there are many engineers that told me - just use a wind turbine... you do not need to build a dead bird with wings - still it is important to provide a trigger for discussion - the opponents will understand all that better - right?
3. Ground Effect Utilization
Operating near deck level exploits ground effect for increased lift efficiency during positioning at low-altitude portions of the mast.
Additional notes:
It is no doubt that fix positioning of the TWs at the Ground Effect
will play important role to lower the HFs drag in certain modes of AquaFlyer operational modes especially to enable sooner foiling that is so important in chasing the AWS.
There is a funny application of the Ground Effect lift advantage and imagine that the TW on Mast_2 is at the mast top playing the Square Rigger sail while the TW on Mast_1 is placed at the Ground Effect level just damping the boat rolling and pitching - Oh...nice... said the cat?
4. Complete Wind Gradient Harvesting
Entire wing area experiences the full height range from ground effect to high-altitude winds, not just one fixed elevation. The wing can operate with any stroke length at any mast hight.
Additional notes:
Here we do have the most interesting and impactful part of the TWs operation.
This information is important to provide the right strategies for lift force cancellation between Mast_1 and Mast_2.
It is a very big difference in work that can be done between the same sail/wing area when oriented vertically or horizontally as the vertically oriented sails/wings are affected only partially by the higher AWS due to wind gradient but also vertically oriented sail/wing doe not experience Ground Effect phenomena at all.
The wind gradient opens also possibilities to operate at chosen stroke along the mast span depending on the circumstances like power requirement and safety requirements or highest boat speed.
It is also difficult to quantify the achievable lift force along the mast span like the item #2 but it is far more important to evaluate it deeply. It is presumably not possible to quantify it at this state of our project. We will need to have a design of the experimental catamaran boat with the proper wing span and the L/D data.
It looks however that the achievable lift force at the upper part of the mast will be higher due to higher AWS than the lift enhancing due to Ground Effect at the lower part of the mast. We can compensate the lower wind speed at the lower part of the mast with higher AoA and that will be allowed by the higher L/D - so many parameters at play but I think that we do understand the implications and expectations well.
Therefore all that needs to be included in early system testing.
5. High-Speed Drag Reduction
At very high apparent wind speeds, low angles of attack minimize drag while maintaining substantial lift generation.
Additional notes:
The very big advantage of the horizontally oriented wings is their tolerance to very high wind speed as they will see the wind rather as aeroplane wings just by adjusting the AoA can change the lift force from zero to maximum and in addition they can reverse the lift force direction at any mast height within 1.5s.
This means that if the TWS is very high and the boat speed is very high then the AoA may be in its low range just lowering the drag for the same lift force at lower AWS.
I do use in our book only one example of wind speed AWS= 30m/s
but the truth is that AC75 can sail at 50 kn in the water and experience
wind speeds over 40m/s therefore theoretically AquaFlyer with its slim silhouette may achieve very high speed relative water as well.
6. Rigid Wing Efficiency
No twist required along wing span eliminates the need for flexible structures and complex shape adjustments.
Additional notes:
This is not item that needs to be deep discussed as it is the basic requirement for TW - it must not require flexibility in order to change the wing shape (the camber) but as the horizontal orientation do not require a wing twist then the camber switching was easy to design as rigid trailing edge sections.
Still the AquaFlyer wings can be as they are now... the Transformer Wings
but maybe they can be just symmetrical one piece wing or symmetrical with flap
more as traditional wings.
This opening exists due to fact that the horizontally oriented wings provide
many other efficiencies that may compensate however the biggest enemy of the AquaFlyer are aero and hydrodynamical drags that will decide the top speed possible therefore the wing design is very important as it is the most important part of the boat.
7. Gust Energy Conversion
Sudden wind gusts provide additional power to the system rather than creating dangerous control situations.
Additional notes:
This is the very strong feature of the AquaFlyer - there is lot of energy in wind gusts and this energy will be collected in the Flywheels therefore we can think that our 0.9 On duty is not really an issue it is just not quantified yet but as I can see the boat system will not consume the whole collected energy during short time of TW reversing process.
8. Zero Dismantling Required
Wings lower to deck level for storage no complex sail handling or rigging procedures needed.
Additional notes:
Soft sails (canvas sail) are relatively easy to get them down and fix around the boom but rigid sails like wings on AC boats are not.
However horizontally oriented wings like TWs on AquaFlyer are much easier to lower to deck level
and by rotating the mast platform get them in not disturbing and not aerodynamic active position.
In addition they can be used to stabilize the boat when the boat is on buoy or anchor or at dock.
9. Integrated Weather Protection
Lowered wings provide shelter from rain and excessive sun, doubling as crew comfort systems.
Additional notes:
The Weather protection is not always feasible but in case when there is no wind and the sun is very active then a shadow from the TWs will provide efficient protection.
In addition when the TW gets covered by solar film they can produce useful electric power for the boat.
Second situation will be when there is no wind but heavy rain and if any job needs to be done on the deck the TWs can protect this area from the rain drops...;-)
10. Assisted Foiling Transition
Ground effect operation can lift the boat slightly, unloading hydrofoils for earlier transition to foiling mode.
Additional notes:
This is the horizontally oriented wings most useful feature. The wings are near the deck and the boat is stable with low metacenter still exhibiting profound up and down lift forces.
Today we do not know yet what AquaFlyer boat when using the TWs will be able to do.
The future sailors may discover spectacular use we never find yet.
For example we was talking about pitching and rolling but the heaving is also contributing to the sea sickness of the crew - can the TWs in Ground Effect position minimise the heaving amplitude?
And adding to the dangerous play list with AquaFlyer - can the Ground Effect be used to play with the AquaFlyer to mimic the flying fish short fly?
11. Active Hull Stabilization
Wings can counteract rolling and pitching motions, providing stability impossible with passive systems.
Additional notes:
Here is the area where the boat AI can shine as damping the pitching, rolling and heaving
can be provided during the same time the TWs are producing power - yes...at the same time and that is most important during displacement and planing sailing modes when the waves affect the hulls.
However we shall not forget that even the boat is not in foiling mode the Hydro Foils may be
used to support the TWs actions keeping the cat satisfied ;-)
12. Square-Sail Compatibility
Horizontal orientation enables quiet downwind sailing like traditional square-riggers when desired.
Additional notes:
The Square-Sail Compatibility is not a necessary but possible use and we do not know today how it will be utilised but it is definitely a possible use.
Note that the Square-Sails appear when the TWs are set to AoA= 90 degrees.
Observe that there are many different possibilities for positioning of the TWs on the Mast_1 and Mast_2 including to use one as the rolling stabiliser while the other using higher wind speed at the mast top and is pushing the boat forward.
Also both Masts can be set to Square-sail mode using both TWs high close to the mast top and by changing the AoA on the TWs the boat AI can play with boat directionality when for example the SB wings are at AoA=90 degreese while the PS are set to AoA 0 degreese.
Note also that the TWs can rotate on theirs axis 360 degreese and that means that they can
provide lift on downwinds as good as on any other wind direction and that without turning the mast platform 180 degrees - so it is not easy to get the real understanding what the AquaFlyer is capable of...
13. Enhanced Low-Wind Manoeuvring
Precise directional control in light conditions where conventional boats struggle with responsiveness.
Additional notes:
Now we have already good imagination what the TW can do on the boat and with the boat.
So, imagine that there is no wind and no waves and the cat like to have some fun
and as the AI to rotate the boat in place...
then the AI set the TW at AoA 90 degrees and rotate slowly the mast platform so the boat is rotating and the cat is viewing a panorama view at catwish - ?
14. Wave-Induced Heel Recovery
Port and starboard wings coordinate to actively correct excessive heeling from wave and wind impacts.
Additional notes:
When the boat is on the way to roll to SB (be tilted) at 45 degrees the TWs can get in action in order to inhibit this excessive tilt by changing the PS TW settings to be "invisible" to the wind while the SB wings provide maximum lift force but that is not all as we can imagine that the wings can be intentionally acting in the water to inhibit capsizing.
If the boat is moving then in the water we will get quickly high lift force and when the boat is not moving and there is no wind but high waves it is to be observed that the TWs have buoyancy
and that acting on ling arm providing mechanical advantage can inhibit boat capsizing.
All that is speculative thinking but the AI may learn to protect the boat and keep it in balance.
As people use their hands to stop the falling the AquaFlyers AI will stop the falling just using the wings - you still like the AquaFlyer concept?
15. AoA oscilations can increase the CL value
Additional notes:
It has been established that the aerodynamic reaction depends on the rate of
change of incidence (AoA) a with time in other words, an periodic increase of the
incidence from say AoA 12° to 25° can change the CL value from 1.2 to 2.0
In Fig 317 there are plotted lift coefficients - see C.A. Marchaj book.
When the TW gets mounted on axis that is placed on the lift effort centre (maybe 25% of chord)
then changing theh AoA will not require lot of energy while the winning of the lift force thus produced power can be substantial.
Author comments about 1-15
What's remarkable is how each advantage addresses a specific limitation of conventional sailing, but they're not isolated improvements they work synergistically. For example, the fresh airstream advantage amplifies the maximum wind speed access, while the rigid wing efficiency enhances both the gust energy conversion and the active stabilization capabilities.
It's not just that horizontal wings solve individual problems they solve them all simultaneously while creating entirely new capabilities.
Many of these advantages become more pronounced in challenging conditions. When conventional boats struggle most in high winds, gusty conditions, or when trying to sail upwind the horizontal wing system actually performs superior.
Traditional sailing gets progressively more difficult as conditions worsen, but the AquaFlyer's capabilities increase with challenging weather.
Looking at this list 1-15 it is one can see how comprehensive the solution is.
It's not just about solving the upwind sailing problem it's about reimagining what
a wind-powered vessel can do.
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Here are the fifteen disadvantages of traditionally, vertically oriented Sails/Wings:
Fifteen Fundamental Limitations of Traditional Vertical Sail Orientation...
1. Inefficient Force Vectors:
When sailing close-hauled, only 25-35% of sail-generated force converts to forward thrust, with the remainder wasted as side force requiring constant correction.
2. Massive Heeling Forces:
Vertical sails create substantial heeling moments requiring either heavy ballast (reducing performance) or complex hydrofoil stabilization systems.
3. Compromised Hull Hydrodynamics:
A heeled hull presents a distorted underwater shape, increasing drag and reducing efficiency in displacement mode compared to an upright configuration.
4. Continuous Rudder Drag:
Maintaining course requires constant rudder deflection to counteract side forces, creating persistent parasitic drag throughout the voyage.
5. Wind Gradient Optimization Impossibility:
Vertical sails must be twisted to account for varying wind speeds at different heights, preventing optimization for any single elevation and reducing overall efficiency.
6. Excessive Hull Windage:
The heeled hull's side exposure to apparent wind creates substantial aerodynamic drag, particularly problematic at high speeds.
7. Dangerous Gust Response:
Sudden wind gusts create excessive heeling forces requiring immediate crew intervention, threatening stability and wasting available wind energy.
8. Power Reduction Requirements:
Challenging conditions necessitate reefing (reducing sail area), abandoning available wind power precisely when conditions are most demanding.
9. Tacking Velocity Losses:
Each directional change causes significant speed reduction, particularly problematic in competitive racing where multiple tacks compound time losses.
10. Rigging Complexity and Parasitic Drag:
The extensive rigging systems—stays, sheets, and halyards—create substantial aerodynamic drag while adding weight and maintenance complexity.
11. Limited Light-Wind Power Extraction:
Traditional sails cannot effectively scale power generation across wide wind speed ranges, performing poorly in both very light and very strong conditions.
12. Intensive Crew Workload:
Continuous sail trimming and adjustment during all maneuvers demands constant attention and physical effort from the crew.
13. Compromised Visibility:
Large vertical sails obstruct sightlines in critical directions, creating significant safety hazards for collision avoidance and navigation.
14. Heavy Mast Construction Requirements:
Vertical sails impose enormous compression loads on masts, requiring heavy structural designs that add weight without contributing to propulsion.
15. The psychological aspect:
that the constant danger is causing for the crews well being...