Does An Aircraft Have A Key? #Jesseyknows

You can lock a car with the push of a button on your key once you’ve parked it. But how does that work with an aircraft? Can you lock it and then start it up again with a key? In short: Does an aircraft have a key? I received this question in a Tweet, so I looked it up.

Picture this: A pilot walks into the Cabin Crew Centre at Schiphol. He fishes around in a great, big cabinet for his key and then makes his way to the gate. He sits down in the cockpit, puts the key in the ignition, and Voila! The aircraft starts right up.

However, this idea was quickly put to rest by Johnny, who works in Engineering and Maintenance. We were sitting in the cockpit of a Boeing 777 parked in Hangar 14. I searched around for the ignition slot under the steering wheel. Johnny laughed. “You can stop looking. An aircraft doesn’t use a key—not to lock the doors, and certainly not to start the engines.”

Keyless Start-up

But if an aircraft doesn’t use a key, how do you start it? It goes like this: Commercial aircraft have a gas turbine generator in the tail, called the Auxiliary Power Unit (or APU for short) which provides the plane with air and electrical power. The aircraft uses the air to start the engines. As soon as the pilot flips the “start” switch in the cockpit, the air conditioning turns off and the air flow is diverted to start the engines.

I asked Johnny where the start switch was and he pointed to a small switch among countless others on the ceiling.

Cockpit KLM

Blowing On the Engines

So, the air flow blows the engines into action. By turning on the fuel switch, fuel flows into the engines and the combustion chamber receives a spark. The fuel combusts and the engine turns, which creates its own air flow, all of which keeps the engine turning.

In modern aircraft, the entire start-up procedure is automatic. The pilot only has to set the start switch to the correct position and turn on the fuel switch. In twin-engine aircraft, the pilot turns on each engine separately.


Don’t any aircraft use a key to start up? Sure! Small aircraft, such as the Cessna, uses a key to lock it and start it up—pretty similar to a car.

Jessey Goes

With this blog I’ll be ending my series of  #Jesseyknows. I was given the opportunity to dive into a new challenge at another company. I hope my stories interested you and made you smile. I had a lot of fun writing the blogs and investigating the (sometimes funny) questions I received via Social Media. Thank you for all the comments, questions, feedback and great ideas. From now, it will be #Jesseygoes ;)

Posted by:   Jessey de Graaf  | 
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You were sitting in a Boeing 777, not a 747 ;)


Thanks for your sharp eye, Flo! It has been corrected! ;)

Muhammad Gillfran

Does that the cockpit of B777?

Gunnar Engesland

But how to start apu?

Dion Robinson

There is a switch on top of the panel that says “APU” and then you switch it on and the APU will turn on.


No key to start an airplane but there is a key to lock the cockpit door from the outside……….


Still leaves the question about locking the plane? If someone with malintent (or confused crew member) can make into the airplane they can start it? I.e. keys are not only used for starting (in fact that is secondary to its security purpose).

Well written article though!


I was seouirsly at DefCon 5 until I saw this post.


But: how are doors locked and unlocked? ;-)

Frank van der Voet

Jessey, your blogs have been very interesting and informative. Best of luck with your new assignment.


Thank you for your kind words, Frank! I’m glad you liked my stories!

Thomas M Bernabela

Dank u wel voor uw informatie. Tot de volgende keer. Ik wacht op antwoord over mijn Airmiles.


Graag gedaan, Thomas! Tot de volgende keer. Ik zie je in februari bent aangemeld voor Flying Blue, maar ik kan geen vraag over airmiles vinden. Mag ik je vragen deze vraag opnieuw via Facebook te stellen? We helpen je uiteraard graag!

Hendrik Martens

Ik vlieg donderdag 19 maart naar Miami en wil een glasservice meenemen in mijn hand bagege. Is dit toegestaan?


Wat een zonnig vooruitzicht, Hendrik! Servies van glas mag je meenemen als handbagage, mits het toegestane gewicht niet overschreden wordt. Alle verboden voorwerpen wat betreft handbagage kun je vinden via deze link:


Hi Jessey,

I’m Nadia from Malaysia.
Love your writing.
As I’m one of aviation industry fans, I’m quite jealous with you to explore so much about aviation.
Would love to join you if possible hehe!

All the best!



Hi Nadia, thank you so much for your compliment! I feel very lucky to be able to explore all these aspects of the aviation industry. If you have a burning question in the future, please don’t hesitate to keep asking them via social media. I’m sure one of my colleagues will find the answer for you! Kind regards, Jessey.

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