The present invention is in the technical area of aircraft, relates to an electrical aircraft with wing-mounted pods and, more particularly, to an aircraft with pods that can be jettisoned from the aircraft.
Electrically-powered aircraft are gaining in popularity as motors and batteries become more efficient. However, efficient batteries use aggressive chemistries that are dangerous by themselves but even more so when they catch fire. Possible solutions include shielding the batteries in fireproof enclosures, designing batteries that don't catch fire, creating cooling systems that keep batteries cool, encapsulating each battery cell to prevent one battery from catching other batteries on fire.
Shielding, however, is heavy, and limits access to batteries. Also, batteries that don't catch fire are typically heavy and inefficient. Further, cooling systems take up valuable space, create drag and add weight. Also, encapsulating battery cells also adds weight and cost.
In one embodiment of the present invention an aircraft is provided, comprising an airframe, at least one electrically-powered propulsion unit providing motive power for levitation and translation of the aircraft, at least one pod comprising a battery, mounted by a physical interface to the airframe, the physical interface operable to detach and jettison the at least one pod, and comprising electrical connectors coupling the battery in the mounted pod to the at least one electrically-powered propulsion unit, and control circuitry operable to manage power from the battery to the electrically-powered propulsion unit, and to jettison the pod.
In one embodiment the at least one pod comprises, in addition to the battery, local control circuitry, an electric motor and a propeller coupled to the motor such that, when the motor operates, the propeller spins. Also, in one embodiment the propeller is enabled to fold into a volume having an axis co-linear with an axis of the motor. In one embodiment the propeller is enabled to vary pitch. And in one embodiment the aircraft is a fixed-wing aircraft, and pods are mounted beneath wings of the aircraft.
In one the pods mounted beneath the wings comprise controls, motors, and propellers, and are manageable through the control circuitry, individually, to start and stop the motors, fold the propellers, and to jettison the pods. Also, in one embodiment the pods further comprise each a parachute controllable to deploy following jettisoning the pod. In one embodiment the fixed-wing aircraft further comprises an electrically-powered motor with propeller separate from the pods, powered from one of more of the pods. And in one embodiment the fixed-wing aircraft further comprises an internal combustion engine with propeller which is enabled to be stopped and feathered with pods powering motors with propellers in operation.
The present invention solves or alleviates a number of problems in the art of aircraft powered by electric motors, necessarily powered by one or more batteries mounted in or on the aircraft. One problem in such aircraft is to have an efficient way to discard or replace batteries that have been drained of power. Another potential problem is that high-power batteries for such application are known to be prone to overheating and fire. It would further be advantageous to provide a way to discard power controllers that may also catch fire. Swapping dead batteries for charged batteries is also a desire.
The pod 20 that is carried under the aircraft fuselage in this example has no motor or propeller. This pod may be just auxiliary power source supplementing the other pods. In embodiments of the invention there are physical interface under the wings and under the fuselage comprising also electrical connectors and conductors, such that each pod location may be connected with others so that any pod may be a power source for electrical motors in other pod locations. In some embodiments, as described above, computerized controllers are incorporated within the pods, and control connections may also be made through the physical interfaces where pods are supported. There may be control circuitry within the cockpit of the aircraft whereby a pilot or other person may manage functionality of pods, including releasing pods, as described further below.
In one embodiment the propellers on the pods are opposite hand, chiral orientation and counter-rotating. The advantage to counter-rotating propellers when attached to the wing is you don't have a “critical” motor. By rotating “into” the fuselage the torque of the motor doesn't tend to roll the aircraft on its back.
It is known in the art that aircraft batteries are electrically wired and connected in series, where the voltage load is distributed evenly or close top even. The problem with this scenario is that if one battery fails, or catches fire, none of the other batteries would operate and the aircraft would fail and cease to fly. In most embodiments of the present invention, the pods are wired and connected in parallel, wherein each pod, with battery, motor and propeller, can operate to fly the aircraft alone, without the assistance of another pod. In this embodiment, one pod is utilized to fly the plane until its charge is exhausted, for example after 45 minutes to one hour, and then it is jettisoned and the next pod is utilized to continue to fly the plane. Alternatively, two pods may be utilized at the same time, or even all of the available pods.
Although fire and safety are main advantages of implementing the present invention, additional advantages are that once a pod is ejected, weight on the overall plane is decreased, drag is decreased, thereby lessening the load wherein each remaining pod can keep the plane in the air a bit longer. Specific calculations for determining fight times v. weight of aircraft, drag, etc. are known in the art. Also, pods may be easily added or switched out for fresh, fully charged pods when the aircraft lands at a designated airport supporting such services.
In some embodiments GPS circuitry is included in pods, so pods may be quickly located and retrieved once having been jettisoned. In other embodiments there may be a homing signal produced by a jettisoned pod. As described briefly above, with the use of self-folding propellers, the propellers may be folded as a first step with a jettison sequence is activated, so the propellers may be less of a problem in descent and recovery of a pod.
The skilled person will understand that the descriptions herein are entirely, exemplary and are not strictly limiting to the scope of the invention. The scope is limited only by the claims.
The present application claims priority to Provisional Application U.S. 62/686,001, filed Jun. 16, 2018. All disclosure of the parent application is incorporated herein at least by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US19/37087 | 6/13/2019 | WO | 00 |
Number | Date | Country | |
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62686001 | Jun 2018 | US |