Cargo Drone: Beihang Unmanned Aircraft System Technology

[TinWing]

https://www.uasvision.com/2018/06/05/china-to-develop-large-payload-cargo-drone/

They plan to finalize their design before year’s end and construct a prototype in 2019 for test flights scheduled to start in 2020. Mass production will begin if test flights are successful, and a drone-based delivery network is expected to take shape around 2025, said Zhang Shuo, chief designer at the Beihang technology company, in an exclusive interview with China Daily.

The yet to be named drone will be so big that if it were to carry people, it easily would hold nine passengers, according to the company.

It will be 11.9 meters long, with a wingspan of 19.6 m, and have a maximum takeoff weight of 3.6 tons. The craft will be powered by two engines and have 16 cubic meters of cargo space.

Before anyone gets too excited, it's worth pointing out that the concept has the same approximate MTOW as a de Havilland DHC-3 Otter, as well as the same 9 passenger capacity.

 

[AeroFranz]

Cool concept, although it seems to lack both horizontal and vertical tail area. The former is particularly important to achieve a useful cg range. The latter is needed to handle engine out cases, which is pretty bad for twin engine designs (see the equivalent fin on a twin otter...).
The dark grey surface at the trailing edge of the 'beaver tail' fuselage may be a trim surface.
It's curious that it seems to have both a hinged nose and an aft ramp.
I'll be curious to see future news about this. Thanks for posting!

 

[TinWing]

Cool concept, although it seems to lack both horizontal and vertical tail area. The former is particularly important to achieve a useful cg range. The latter is needed to handle engine out cases, which is pretty bad for twin engine designs (see the equivalent fin on a twin otter...).
The dark grey surface at the trailing edge of the 'beaver tail' fuselage may be a trim surface.
It's curious that it seems to have both a hinged nose and an aft ramp.
I'll be curious to see future news about this. Thanks for posting!

I think that the concept minimizes the number of control surfaces for the sake of unit costs. If you notice, there's a relatively large trim tab in back, which presumably would manage center of gravity issues for load outs of rather light parcels. We're nowhere near the certification of unmanned passenger aircraft.

Engine out performance really depends on the MTBF for the inevitable small scale turboprops or diesel cycle engines and the acceptable level of operational attrition. I found this concept while searching for applications of the 240hp PBS Velko turboprop, although it's not mentioned in the article and the engine cowlings are ambiguous in shape. I'm not sure why searching for a small turboprop brought this up, although maybe there's more information in a Chinese language source which influenced the SEO of this page.

It's early days for turboprops smaller than the Allison/RR 250, but that seems like the future of general aviation. What is the MTBF for a PBS TP100 compared to a comparable Continental AVGAS engine? What's the service life for the little TP100? AVGAS opposed cylinder motors always do less than 2,000 hours between overhauls? I don't know much about adapted diesel automotive engines from Austro Engines (Thierlet), although there must be a couple thousand in service in Diamond aircraft by now. They claim a 100,000 hour MTBF but overhauls still come every 1,800-2,100 hours, which is unremarkable compared to ancient AVGAS motors.

 

[TomS]

Looks like the nose is the main means of access. The tail might not even have a ramp, just a beavertail for aerodynamics?

 

[AeroFranz]

hmm...you're probably right. There's a bit of tapering of the top fuselage going aft towards the tail, it would be hard to slide a container aft. Especially once the front corner starts tipping down the (alleged) ramp and the back corner of the box moves up.

I like the engines coming out of PBS Velka, but it's early to say anything about their reliability. I am digging the TJ100 installation on the SubSonex, though!
IMHO, the smallest trustworthy gas turbine would be the RR300 (as used by the Robinson R66), just by virtue of the RR250 heritage and the brand behind it. Back when it was first launched, Rolls said they'd make a turboprop version of it, but i never heard anything since, sadly...
The US Army has a small turbine program going on called reliable advanced small power systems (RASPS), aimed at introducing a 200 shp engine to replace the Diesels on Gray Eagle. They've awarded a couple of companies, IIRC, but remains to be seen where that will lead.

 

[TomcatViP]

But why a swept wing if the beaver tail is actuated?

 

[Sundog]

But why a swept wing if the beaver tail is actuated?

For good Dutch-Roll (Roll Yaw coupling) behavior, since it's really just a flying wing with a big trim tab at the back; similar to the B-2 in that regard.