What are modals of possibility?
When we want to talk about things that are possible but not certain, we use three key modal verbs: could, might, and may. Unlike will, which expresses certainty, or must, which signals obligation, these three modals leave room for doubt.
They appear constantly in professional aviation English — when pilots and controllers discuss possible outcomes, when journalists report on emerging technologies like eVTOL aircraft, and when regulators outline future rules. All three are interchangeable in many contexts, though there are subtle differences worth knowing.
How they work
The formula is simple: subject + modal + base verb.
- The aircraft could carry up to five passengers.
- Services might begin later this year.
- Regulators may require further tests before approving commercial flights.
All three sentences express possibility — something not guaranteed. Notice that the verb after the modal stays in its base form (carry, begin, require), with no -s, -ing, or -ed ending.
Could, might or may — any difference?
In most everyday contexts, these three modals are interchangeable for future possibility. A few patterns are worth noting:
- Could often suggests a theoretical capacity: “The eVTOL aircraft could transform city transport.”
- Might and may both express an uncertain prediction. May tends to sound slightly more formal: “Regulators might / may require additional tests.”
- In conditional sentences with if, could and might are the natural choices: “If Joby receives certification, it could begin services in 2027.”
Fill in the gaps
Each sentence below is based on the story of Joby Aviation’s eVTOL air taxi. Fill in each gap with a modal of possibility: could, might, or may. All three may work in some gaps — choose the one that sounds most natural to you.
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Joby Aviation’s eVTOL aircraft ______ carry up to four passengers on short urban routes.
All three modals of possibility work here. ‘Could’ also hints at the aircraft’s technical capability.
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The company says fares ______ eventually be as low as a regular ride-sharing app.
These modals express an uncertain future prediction — we don’t know for certain what fares will be.
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The cost of FAA certification ______ slow down the introduction of affordable passenger services.
An uncertain possibility — we cannot say for sure whether this will happen.
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If the FAA grants the type certificate on schedule, Joby ______ begin commercial services as early as 2027.
In a conditional sentence (‘if…’), ‘could’ is especially natural to express a possible result.
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Competing companies like Archer Aviation ______ also reach the market around the same time.
This is a genuine uncertain prediction — the speaker doesn’t know what rivals will do.
CEFR Level B1 / ICAO Level 4
You will find more examples of modals of possibility throughout our CEFR B1 archive — aviation stories at this level regularly use could, might and may when discussing new technologies and regulatory decisions.