Choosing a VTOL Fixed-Wing UAV: Payload, Endurance and the Questions That Decide It

A VTOL fixed-wing aircraft is bought for one reason: it removes the runway without giving up the range. Everything else — payload, endurance, cruise speed, the data link — hangs off that idea, and the numbers on a specification sheet do not tell you which compromise the designer made to get there.

This note sets out the questions we ask when a buyer tells us a mission rather than a model number.

Payload and endurance are the same number, read twice

Maximum payload is usually quoted at a reduced endurance, and maximum endurance at a reduced payload. An airframe rated for a 190 kg payload at a 470 kg maximum take-off weight will fly about 5 hours carrying that full payload — the figure changes as soon as you take payload off or add it on.

So the useful question is never "what is the payload?" but:

What is the payload at the endurance I need?
What is the endurance at the payload I need?
Which of the two am I actually willing to give up?

If a supplier quotes a payload figure and an endurance figure in the same breath without stating the relationship between them, ask for the curve, not the point.

Start from the mission, not the platform

Three numbers decide most selections. Write them down before looking at any catalogue.

Line length or area. A 2-hour line patrol along a transmission corridor and a survey of a 200-hectare site are different problems in the same category.
Sensor mass. A gimbal with a 40x zoom block and a laser rangefinder is a different load from a fixed mapping camera, and the mass sits in a different place on the airframe.
Launch and recovery space. A clearing of a few metres always, or a proper strip sometimes? If it is "always", the VTOL decision is already made.

A platform such as the AT-G10, rated to a 10 kg payload, suits repeated line patrol work where the sensor is modest and the sortie is short. A heavy-lift airframe such as the AT-G190 exists for the opposite case: a payload mass — a heavy sensor, a delivery load, a multi-sensor turret — that simply cannot be lifted by a smaller wing.

The data link is part of the aircraft

A platform's operational range is the shorter of its endurance and its link. Two aircraft with identical flight time are not interchangeable if one carries a 15 km link and the other a 30 km one.

Three points worth pinning down:

Frequency and regulation. Our AEROLINK series run on 1.4 GHz with real-time spectrum sensing and frequency hopping, and support custom bands. Whether 1.4 GHz is legal, at what power, is a question for the destination country — the buyer holds the licence.
Nodes. If the mission involves relaying, the number of supported nodes matters more than the headline range.
Latency. Video latency decides whether a human can fly it or only watch it.

What to ask about the ground side

The ground control station is the part buyers most often leave to the end, and the part that limits the fleet. A station rated for 30 km of combined control and video on a sunny 10.1-inch screen is a different proposition from a handheld controller, and the difference shows up on the second aircraft, not the first.

Ask whether one GCS can serve the fleet you plan to own in two years, or only the aircraft you are buying today.

Compliance is a procurement item, not an afterthought

Export licensing is the buyer's responsibility: the purchaser obtains export qualifications and licences, and provides end-user documentation. A quotation that ignores this is not cheaper, it is just incomplete.

Two things follow:

Confirm the product may be lawfully imported, possessed and used at the destination.
Ask for the specification sheets and configuration lists in writing early. They should arrive before the goods, not with them.

A short checklist

Before you commit to a platform, you should be able to answer all of these:

Payload at the endurance I need, and endurance at the payload I need.
Link range and the regulatory position at the destination.
Launch and recovery footprint on the worst site, not the best.
GCS capability across the fleet, not just one aircraft.
Export licensing route and the documentation package.
Spares and warranty terms for the specific configuration.

If a supplier cannot answer most of these in writing, the missing answers will be found by your operations team instead.

If you would rather describe the mission than read another specification sheet, send us the line length, the sensor and the terrain — we will tell you which platform fits and which one does not.