Fixed Wing Drones: When it is a better option.
Drone Flight times
Fixed Wing Drones vs. Multirotor Drones and the 1 hour barrier.
A discussion about the ‘comfort zone’ of long range Quadcopters vs the competitive value of Fixed Wing UAVs at the higher-end where quadcopters hit the ‘1 hour flight-time limit’.
WIDE SCALE ADOPTION of UAVs
Drones, or UAVs, have now been around for quite a while and there are a number of indications of the market progressively moving through the traditional Technology Adoption S-curve. Recent research shows that nearly 90% of the market still prefer multi-rotors, probably in part influenced by the futuristic visions of skies filled with buzzing multi-rotor drones. However the pronounced shift across the market to more expensive, and longer endurance, drones cannot be ignored.
THE QUADCOPTER ‘COMFORT ZONE’
First experiences
To start off with most UAV users have been attracted to the cheaper, easier to use, off-the-shelf personal quadcopters. Today most multi-rotors fly for 25 minutes, or less, and have a limited range of only a few kilometres with concomitant price tags of only a few thousand dollars.
Long range
At the higher end, a few multi-rotor UAV manufacturers have managed to approach, or exceed the 1 hour flight time mark – UAVs in this bracket can be in the $100k price range. As the familiarity with aircraft grew, and the value of drones became more apparent, the need for bigger and better drones also grew. As market statistics show, the preoccupation with quadcopters persisted.
The 60 minute barrier
It seems though that 60 minutes is an inherent limit for multi-rotor UAVs given the natural laws of physics. Some design alternatives to overcome this limit have been to switch to petrol driven motors, or replace the actual airframes of the UAVs with batteries. These also come with their own limitations.
MULTI-ROTOR MARKET DRIFT
Horses for courses
MULTI-ROTOR/ FIXED WING DRONE MARKET OVERLAP
The lightweight fixed-wing UAV market can loosely be categorised as shown in the table below:
| Wingspan | MTOW | Payload | Min price | Max price | Hours | Kms |
|---|---|---|---|---|---|---|
| Multi-rotor | 12kgs | 1,2kgs | $75 000 | $100 000 | 1 | 35 |
| FW 1,5m | 3,5kgs | 0,5kgs | $55 000 | $250 000 | 3 | 150 |
| FW 3m | 25kgs | 5kgs | $250 000 | $500 000 | 3 | 150 |
| FW 6m | 100kgs | 25kgs | $35 000 000 | $35 000 000 | 25 | 150 |
(This table excludes cheaper models of a more disposable nature.)
As can been seen from the table above, some of the fixed-wing drones are in the same price range as the higher end multi-rotors. Not only are the price points comparable; the relevant fixed-wings also have the advantages of providing up to 6 times the flight range, 3 times the flight time and up to 10 times the payload capacity of the multi-rotor. With this fixed-wing drones are also able to carry powerful sensors which, along with superior gimbal stabilization, provide better images than the maneuverable multi-rotors.
Gone are the days where fixed-wing drones were only associated with military applications and complex to operate. Many more long range drones’ commercial applications are beginning to take advantage of the more natural aerodynamic characteristics of fixed-wing drones. Users have also come to realise that all long range missions need planning and a certain minimum level of setup, whether it be multi-rotors, or fixed-wings.
CHANGING LANDSCAPE FOR LONG RANGE DRONES – KEY FEATURES
- Commercially oriented payload experience of multi-rotor manufacturers is now being brought to bear in smaller fixed-wing drones, thereby dramatically increasing their areas of application.
- A key element of the TCO (Total Cost of Ownership) evaluation of multi-rotors is that: for the same overheads you tend to get a shorter life span given that there are more moving parts under high-powered stress, in comparison to fixed-wing drones.
- For long-range flight missions the only practical way to get past the 1hr flight time limit meaningfully, is with aerodynamic efficient fixed-wing drones which have been designed for long range flights to start with. (It is a bit like asking a bodybuilder to perform like a marathon-runner.)
- Generally lightweight fixed-wings nowadays have same learning curve as high endurance commercial quadcopters, but is a better and more enduring investment for skilled staff.
- VTOL: Many fixed wing come with VTOL capabilities that removes the risk of take-off and landing as well as the need for landing strips.
Maybe now is time to break down some of these psychological barriers in order to make this necessary and inevitable make a mind-shift?
Read more about the competitive NEXTECH ATLAS-V option.
