
The above semi-buoyant dirigible aircraft (LS-L50) was drawn 2014 as an omni-directional (O-D) air-lugger for useful ad-hoc aerial-crane lift and transport duties with up to 5 tonne (5000 kg) payloads operating in a similar way to helicopters (but much longer range/endurance), intended to be within existing Commuter category certification rules – limiting development costs.
At ground level, its Ø50 m variable geometry lenticular aerostat is similar in elevation (viewed from the side) to an SKS500 airship’s profile but, when moored, only occupies 25% of the ground area needed (due to fixation). In addition, it has a max geometric volume of 20,400 m3 compared to the SKS500’s 5,130 m3, so gets near 4 times the buoyancy, one of the reasons it will lift so much more. Note also, its ability to access small locations for pick&put duties, not easy for the SKS500 to do.
Payload and Pod

The payload and dirigible’s pod (the main module for crew, systems and equipment) are suspended from the aerostat by an external method spreading load more evenly and simply than is possible for traditional airships with a close coupled gondola. This enables operations without danger of breaking the aerostat’s back, a difficult problem to solve for the US Navy’s YEZ-2A airship.

The LS-L50 arrangement was configured with 8 cycloidal propellers, 4 around the aerostat and 4 around the pod, all able to direct thrust in a horizontal or vertical direction up or down – so designed to overcome significant differences between weight and buoyancy, and to control flight.
This is notional until test flights at full scale are undertaken to properly assess configuration matters and operating needs for the type, which is being determined from small types. The pod also has underfloor ballast tanks sufficient for load exchange, although LSL is working to remove the need.
In addition, freight may be carried in a similar way using a lightweight container (as shown on the right-hand side of the enlarged pod view), simply picked-up or set-down wherever desired.
Benefits of the design are endurance and ability to scale-up for considerably more lift (factors > 10), not possible for helicopters.
Costs and time to develop the design should be less than an equivalent helicopter. For further information, see its leaflet.
Statement Concerning Development
The LS-L50 currently isn’t scheduled for development as it needs a number of key technology and ground infrastructure aspects to be worked out/set in place first. It also needs people trained and ready for operating duties, enabled by smaller types. Sizing also may change, depending on airworthiness acceptance limits for Commuter Category aircraft.
This isn’t to say it’s impossible or can’t be considered yet, as dirigibles in this size/category have been successfully developed and entered service from scratch before. However, where are they now? Show us the type certificate for a buoyant aircraft with a CofA currently in service and able to vertically-lift/transport 5 tonne or greater underslung payloads over 2000 km! Apart from pipe dreams, LSL is confident that there aren’t any.
Sure, there are helicopters that can fulfil this need at the moment, so there’s a way for people to fulfil their relatively low-weight aerial-crane needs; but at what cost (not just money) and how will they be developed for say ten times (10 x) that amount, which buoyant aircraft can. The fact that there aren’t any buoyant aircraft able for such duties while there are people paying for gas guzzling limited range/endurance/payload helicopter aerial-crane services is evidence of market need for better ways, and where aerial-cranes for heavier payloads (say for wind-turbines) are left wanting.
We are interested to hear from people with real needs for serious aerial-cranes to register their interest and begin the dialogue to see how our Strategy for such buoyancy assisted O-D types may be fulfilled in quicker ways. While saying this, we are mindful that numerous people with considerable power and money so far have wasted their time with serious losses. We think they will continue in this way if the pattern isn’t broken.
We therefore say that it’s time for a new way to go, which Luffships provides. After all, our team players are the only people in the world to successfully lead the technical effort for a buoyant aircraft that did vertically air lift and was used over a 2 km course to carry a tank weighing c50 tonne. By comparison, 5 tonne is just a walk in the park. Please go to contact to register interest.