How to Read an Aircraft Specification Sheet

How to Read an Aircraft Specification Sheet

July 14, 2014

When you are in the process of finding an aircraft to purchase, one of the first things that is sent to you is the aircraft specification sheet which at first glance can be quite daunting and confusing. There is a lot of aviation vocabulary and technical jargon that doesn’t always make sense to someone outside the industry. Here is a break down of the basics for you to look at and understand, and gain confidence when you look at a specification sheet to decide if you want to carry on considering that aircraft or not.

Total Time and Total Cycles
The first thing on most spec sheets is the aircraft total time and cycles. “Time” refers to how many actual hours the aircraft has flown which is why this can also be referred to as aircraft hours. Cycles is roughly how many times the aircraft has landed which is why this can also be called aircraft landings. (There are some slight differences between engine cycles and airframe cycles, but ask your aircraft professional to explain these).

Times and Cycles give you an idea of the aircraft’s history. If it has high time then odds are it has been heavily chartered. Or if it has high cycles you will know the aircraft was operated on short routes, meaning it wasn’t flying long flights but short ones and landing frequently. The common perception is that high time/high cycle aircraft are going to need more maintenance. This is not always the case, but if you really like an aircraft with higher hours spend some extra time on aircraft research as the higher time will often mean the aircraft is closer to a major inspection.

Compliance and Certification
On the whole, the aviation world follows two main regulatory streams- the European Aviation Safety Agency (EASA) and the Federal Aviation Authority (FAA). In a very broad explanation, while your local Civil Aviation Authority has their own regulatory rules, they are most often based on either FAA or EASA rules. Knowing the certification is absolutely essential in looking at an aircraft. The avionics requirements for each certification are different, as well as the requirements for which documents they each find acceptable. The difference in equipment alone can go as far as hundreds of thousands of dollars, and making the changes to switch certifications can keep an aircraft on the ground as long as a few months. It doesn’t mean it cannot be done, and it isn’t always a lot of time and money, but it is a factor to consider.

As a side note, it’s much easier for an EASA registered aircraft to go to the FAA register than vice versa.  If we have a European client choosing between very similar aircraft except one is FAA registered and the other is EASA, we give higher preference to the EASA aircraft.

Engine and Airframe Programs
Many aircraft are enrolled on an engine and/or airframe maintenance program. In brief, these are programs you typically pay into per flight hour you use. These are a form of insurance against the cost of maintenance and/or parts on the engines or the airframe. As with many types of insurance programs, there is a plethora of coverage packages available ranging from full coverage for all events and parts to coverage for only unscheduled events or selected parts.
Typically every engine/airframe manufacturer offers their own program, and there are also a few independent providers out on the market. Engine, Airframe, and APU programs with labels like Platinum, Enhanced, Gold, or Elite are usually those with full coverage, as opposed to labels like Basic or Silver which offer more limited coverage. When it comes to a maintenance event, the difference between the programs can be thousands of dollars, so knowing what the program does and does not cover is important. Equally important to the coverage is how the expenses are shared when it comes to a maintenance event. Some independent providers offer Pro-Rata coverage which in essence means late enrolment equals costs shared between the owner and program provider.
It’s important to know if there is an engine or airframe program and what kind it is to know what you will receive and continue to use. There is often an expensive enrolment fee for these programs, so to have the aircraft already on one can save you money.
For more information on engine programs, see our article Transferring Maintenance Programs in the Sale Process

Maintenance and Inspection Status
No one wants to buy an aircraft and head straight into the nearest maintenance shop for heavy scheduled work to be performed. Take a look at the current maintenance status as well as upcoming checks and inspections. Knowing what inspections are soming due or what has been done will give you a good idea of any costs coming down the road. The aviation world recognizes Cescom, CAMP or GCMP maintenance tracking systems as industry standard. When you narrow your search down, your aircraft advisor should look at this report in detail for more information on the specific aircraft’s maintenance as oversights in the maintenance status can become very costly.

This is probably one of the more enjoyable and straightforward things to look at in a spec sheet. The floor plan and layout is important, because it outlines the way you are going to be able to use the aircraft. Will you be using it mainly for business trips so you need the club seating arrangement? Will you be flying with your family and kids most of the time so a divan for sleeping is important?

The cabin media equipment also pre-defines whether you are going to be able to use it for small presentations (monitors/displays with VGA or HDMI ports) or just for watching movies in the DVD player. Internet connection with WIFI signal is becoming more common now, but bear in mind this is still fairly new to aviation so the speed is slower than at your office or home and bills will be significantly higher than your home connection.

The equipment in the galley is going to make your flight more comfortable. Microwaves and high temperature ovens are usually standard in the large, stand-up cabins. In the mid to small cabins, the choice of in-flight meals and refreshments gets more limited to canapés, sandwiches, fruits, etc. and self-service only (In the light-jet category, there is no jump seat for a cabin attendant, so should you choose to take an attendant with you, they will be in one of the passenger seats). These are things to keep in mind when you are prioritizing your wants vs needs in choosing your aircraft.
And of course, look through the interior pictures. It’s easier to envision yourself in an aircraft when you like the colour of the seats or the wood veneer in the cabin. Most things can be changed at a cost, but you might really like what is currently in the aircraft.

This is the 30,000 foot take on assessing an aircraft specification sheet, but it will give you enough information to decide if this aircraft can potentially suit your needs or if you should continue looking elsewhere. As always, never be afraid to ask your aircraft broker any questions you have on understanding what you are looking at.  Aviation is not your main business, so you should not be expected to know the finer details of what TCAS or Hot Sections are.


Articles are written from real world experience by Colibri Aircraft’s individuals. If you have any questions or comments about the topic of this blog, please feel free to contact our team at