The list of things that can go wrong on an aerial shoot are almost endless. The secret is to properly prepare the things you can control - and have contingencies for those you cannot.
First and foremost is to select a qualified, experienced, professional aerial service. Here are a few suggested qualifying inquiries:
1. Ask for relevant references for work of similar type using equivalent cameras and glass.
2. Clearly understand what type of insurance they provide. A world-class company will have no problem providing adequate third-party liability insurance. If the company asks you to split or cover the cost of their equipment, should an incident occur, this is a warning sign that you may not be working with competent professionals.
3. Ask to see raw, unstabilized footage of the types of shots you require, using the exact camera and glass you plan to shoot on.
4. Ask about their fleet. Remotely piloted camera rigs are complex machines made up of a myriad of electromechanical devices. If they only have one platform, this would be cause for concern. It is not practical to have every possible spare component on hand, much less the time needed to install and test. Even worse, should even an minor incident occur, your plans for aerials could quickly evaporate.
5. Don't fall for the "camera bait and switch". Many aerial video websites will indicate that they "can fly" the Red Epic for example. But when pressed to task they will quickly attempt to sway the prospective client to a DSLR. You don't have to settle for less. If all there shots are short and close, and you require a longer, continuous shot, this may be a warning sign that they do not have the confidence or experience to pull off long range shots with a cinema camera. See item 1 above and keep looking.
6. Ask for a copy of the pilots resume and professional flight experience. Statements like "3 years flying experience" is not much assurance. Sport flying at the local model club and flying on a movie set are worlds apart and very different skill sets. What really matters is actual flight hours shooting aerials. If the only platforms they have experience with are octocopters, then their experience is likely limited, as these platforms have only recently become viable tools for filming.
It is also important to gain an understanding of the equipment's limitations:
1. For the camera stabilization to function properly, the camera must be perfectly balanced on
every axis. If the aerial service has not flown the exact kit previously, time will be required in
advance to make all the necessary adjustments. Often even a filter change can upset the whole
apple cart. The most capable operators will have the capability to cover a wide array of cameras
and glass.
2. What is the flight time of the aerial rig? If electric powered, are enough batteries available to
fly/recharge on a continuous basis?
3. If the shooting location is prone to wind, ask for raw footage examples shot in windy conditions.
Also, the larger the rig, the better it's ability to hold position in the wind.
4. Ask about the range of motion for the camera gimbal. For example, almost all multicopters
suffer from very limited tilt range. With a wide lens, the frame tubes will come into camera frame,
even at a level tilt position. This can be a real problem for a variety of shots.
Last but not least, try to get a feel for the companies commitment to safety. Ask for a copy of
their safety manual. Ask them to outline their emergency procedures in the event something might go wrong. And do the entire industry a big favor and don't ask for shots requiring
overflight of large crowds. The entire flight path should be considered an exclusion zone as
far as the general public is concerned.
