Ukrainian army receives new drones and ships – ISW
August 6, 2024
Ukrainian army receives new drones and ships – ISW
by SoftwareExact9359
2 comments
The Ukrainian Ministry of Defense has signed agreements with defense companies to produce new weapons and strike drones, aiming to expand the domestic defense industrial base, according to a report from the Institute for the Study of War (ISW).
The image shows a very conventional WW2 style bomber in miniature drone form.
It’s a logical design but it can be improved upon. If it’s a single use drone or a drone intended to be wire or net caught at the end of its mission, like some delivery drones do, then it can be improved by adding wing tip propellers, pusher or puller configuration.
In pusher configuration, one designed using a flying wing with wing top propellers gained 10% in efficiency. This is almost certainly due to disturbance of the vortice produced as part of ‘lift induced drag’. Many very short wing span plane designs have also used wing tip propellers to get more lift out of a given sized wing, and Nasa has a very high efficiency design with leading edge small propellers along the wing and larger wing top propellers.
Another advantage of this is that you can remove vertical stabiliser and control surface in the tail, yaw comes from the difference in thrust controlled electrically. Thus can reduce visibility and maybe another 10% of drag.
Tge reason you don’t see these, except in high wing, small wingspan designs, is because during take off or landing, propeller strike if the plane rolls leads to increased instability and a certain crash. The original Eviation Alice plane concept had pusher wing tip propellers and superior calculated performance, but has been axed for regulatory compliance. This isn’t an issue with drones.
A pusher propeller also at the back of the drone is highly efficient and may be vertically able to vector a few degrees, this can remove the tail horizontal stabiliser. Again there is less drag, but higher propuksive efficiency because as the plane cruises air flow over the body accelerates with the plane, but pushing this air via a pusher propeller gives greater efficiency and the propeller can be better orientated to increase forwards vector thrust via lift in the forwards direction.
Additional developments have occurred increasing propeller efficiency in the last few years, by unloading propeller tips. This reduces noise as well.
Tge advantage of twin emotor or the above described layout is also that you have the nose and fysilage free to install rockets, pneumatic mortar with small grenades. Sniper rifles, and a camera system in the best position without obscuration.
2 comments
The Ukrainian Ministry of Defense has signed agreements with defense companies to produce new weapons and strike drones, aiming to expand the domestic defense industrial base, according to a report from the Institute for the Study of War (ISW).
The image shows a very conventional WW2 style bomber in miniature drone form.
It’s a logical design but it can be improved upon. If it’s a single use drone or a drone intended to be wire or net caught at the end of its mission, like some delivery drones do, then it can be improved by adding wing tip propellers, pusher or puller configuration.
In pusher configuration, one designed using a flying wing with wing top propellers gained 10% in efficiency. This is almost certainly due to disturbance of the vortice produced as part of ‘lift induced drag’. Many very short wing span plane designs have also used wing tip propellers to get more lift out of a given sized wing, and Nasa has a very high efficiency design with leading edge small propellers along the wing and larger wing top propellers.
Another advantage of this is that you can remove vertical stabiliser and control surface in the tail, yaw comes from the difference in thrust controlled electrically. Thus can reduce visibility and maybe another 10% of drag.
Tge reason you don’t see these, except in high wing, small wingspan designs, is because during take off or landing, propeller strike if the plane rolls leads to increased instability and a certain crash. The original Eviation Alice plane concept had pusher wing tip propellers and superior calculated performance, but has been axed for regulatory compliance. This isn’t an issue with drones.
A pusher propeller also at the back of the drone is highly efficient and may be vertically able to vector a few degrees, this can remove the tail horizontal stabiliser. Again there is less drag, but higher propuksive efficiency because as the plane cruises air flow over the body accelerates with the plane, but pushing this air via a pusher propeller gives greater efficiency and the propeller can be better orientated to increase forwards vector thrust via lift in the forwards direction.
Additional developments have occurred increasing propeller efficiency in the last few years, by unloading propeller tips. This reduces noise as well.
Tge advantage of twin emotor or the above described layout is also that you have the nose and fysilage free to install rockets, pneumatic mortar with small grenades. Sniper rifles, and a camera system in the best position without obscuration.