Bone-in chicken thighs in an air fryer

What usually goes wrong

Skin that never crisps, over meat that is technically safe. The fat under the skin has not rendered, and the usual response — turning the heat up — sets the skin over unrendered fat instead of driving it out. More time at a moderate temperature is what fixes it.

Running the appliance safely

These apply to every food and every air fryer, so they are here once rather than repeated under each state above. They come from Electrical Safety First, from UK product-safety notices and from the manufacturers’ own manuals.

• Plug an air fryer directly into a wall socket. Do not run one from an extension lead.
• An unusual smell, an unusual noise, or scorch marks on the plug mean stop using it and contact the manufacturer.
• Do not overfill. Food touching the heating element is a fire risk, not a cooking problem.
• White smoke from fatty food is usually normal. Black smoke means unplug it immediately.
• Do not leave an air fryer running unattended.
• Leave clear space above and around the appliance, and never cover the air intake or the outlet.

• Aim for a golden yellow colour or lighter on starchy foods such as chips and roast potatoes, rather than a darker brown.
• Buy from a reputable retailer rather than a third-party marketplace seller.
• Clean the drawer, the plate and the element after use. Accumulated grease is what smokes, and then what burns.
• Register the appliance with its manufacturer. It is how a recall reaches you.
• Do not rely on the appliance's own thermal protection. A UK recall was issued because it did not operate.

Each links to its own page, with what it means in practice, what to do if it has already happened, and the source it comes from. Every safety rule AirfryerHQ holds.

Why chicken behaves this way

Lean chicken muscle holds little intramuscular fat, so once its water has gone there is nothing left to keep it palatable — which is why a breast passes from juicy to dry within a couple of minutes and a thigh does not. Skin behaves as a separate material: it needs sustained heat and dry air to render its fat and crisp, and it will stay flabby at a temperature that cooks the meat underneath perfectly well. Bone conducts heat slowly and shields the meat around it, which is why bone-in cuts finish later than their weight suggests.

More on chicken

Where to go from here

The pages that answer the questions this one tends to raise.

• Using a thermometer, and where to put itThe times above are for a piece that is not the one you are holding. This measures yours — and it is the single change that fixes most dry bone-in chicken thighs.
• How food actually gets crispyWhy patting it dry, spacing it out and a little oil are all the same instruction — so you can apply it when a page runs out.
• Cooking from frozenUsually cooler and longer than the same food fresh, and never worked out from the fresh figure.
• Reheating leftoversA different question governed by a different rule — steaming hot throughout, and only once.
• Why published timings differIf another chart says something else, this is usually why — and which one to believe.

If it went wrong

The ways bone-in chicken thighs specifically tends to fail, each with the fastest thing to check first.

• Grease or liquid leaking from the appliance — Liquid escaping the chamber of a mains appliance is not a mess to be wiped up and forgotten. Find out where it came from.

Easily confused with

• Chicken thigh — A different cooking problem with a different answer.
• Chicken drumsticks — A different cooking problem with a different answer.