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Some people seem to believe that some airplanes are less safe to fly just because they are older than others. As a pilot myself who has learned that the safety of aircraft is nothing to do with their age as long as they are properly maintained in accordance with the regulations regarding airworthiness, I take the idea to be wrong and try to talk those people out of their idea whenever I come across them. Some people are persuaded but some are not.

I believe there are nothing better than brute facts in changing one's belief and here is my question: Are there statistics that support the idea that old aircraft are no less safe than new aircraft?

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    $\begingroup$ Regarding your belief that that's "nothing better than brute facts in changing one's belief": have a look at changingminds.org. There is a whole lot better than brute facts, and a substantial body of research suggests that facts can be counter-productive. There is, for example, a well-known bias in which we more easily disregard information that doesn't fit our current opinion/worldview, whereas we do accept information that confirms what we already believe. $\endgroup$
    – Bram
    Jan 26, 2019 at 10:35
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    $\begingroup$ Regarding the content of the question (especially the clarification given in your comment on user71659's answer): I don't know of a database that readily provides the information you're looking for, but using the production lists of popular (commercial) airliners on Airfleets.net you might be able to make such a statistic yourself. You can sort the lists to find all s/n that have been "written off", then compile an Excel-sheet of first flight and crash date, compute the difference and see whether there is a trend. $\endgroup$
    – Bram
    Jan 26, 2019 at 10:41

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I could not find statistics, so I parsed the data available on https://aviation-safety.net/database. This site does have a statistics page, but it does not have an answer to your question.

I'm not a statistician so I'm sure there are much better ways to crunch and graph this data, but the raw data I found was:

  • The data includes 5075 crashes from the years 1919 - 2019.
  • The mean aircraft age is 15.58 years. This age is the age of the particular aircraft involved in the crash, not the "age" of the aircraft's type.

I did not normalize the data in any way, so take it with a grain of salt and except some skews and outliers (for example, a 75 years old DC-3 crashed earlier this year - https://aviation-safety.net/database/record.php?id=20190121-0). On the other hand, crashes in the early years will naturally skew the data, as every aircraft that crashed was new at the time of the crash.

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There is no correlation

... except in Africa:

The analysis indicates that there is no correlation between the fatal accident rates and aircraft age up to 27 years of age for commercial jet aircraft with a MTOW greater than 60,000 lbs. Above this age there was a slight increase in the fatal accident rate but the accident rate data is less reliable for these older aircraft cohorts due to the limited exposure. When all accidents are considered there is no correlation between accident rates and age up till 18 years and a weak trend of increased accident rate with age is observed for aircraft older than 20 years. This increase in the worldwide accident rate is driven mainly by Africa which exhibits a statistically significant increase in accident rate for aircraft older than 20 years. Other regions such as North America and Europe do not exhibit any correlation of accident rate with aircraft age.

Source: Hansman, R. J. "Analysis of Impact of Aircraft Age on Safety for Air Transport Jet Airplanes." International Center for Air Transportation (ICAT), Massachusetts Institute of Technology: Cambridge, MA, USA (2014). (PDF)

Side note: that age (~27 years) matches the average retirement age of jetliners (in passenger-carrying capacity). (ICAO)

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    $\begingroup$ I suppose it is not controlled for operator quality (because how does one even measure it). So the correlation is likely driven up by operators with low budgets and poor maintenance operating second-(third, fourth, fifth…)-hand aircraft, which are most common in Africa. So still nothing to do with the age itself, just old aircraft being more often poorly maintained. $\endgroup$
    – Jan Hudec
    Sep 4, 2021 at 17:23
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The answer is no. Statistics show that new types have lower accident rates than older types.

Airbus has grouped aircraft into 4 categories: early jets, autopilot jets, glass cockpits, and FBW jets. They state

The lowest sustained fatal accident rate of first generation jets was around 3.0 accidents per million flights, whilst for the second generation it was around 0.7, meaning a reduction of fatal accidents of almost 80% between generations. In comparison, third generation jets now achieve about 0.2 accidents per million flights, a reduction of around a further 70%.

Finally, fourth generation jets have the lowest accident rate of all, at a stable average rate of about 0.1 fatal accidents per million flights, which is a further 50% reduction compared to the third generation.

They provide charts (page 17) which show that the accident rate of FBW planes is half that of third-gen glass cockpit planes over the last 10 years.

New aircraft have features like auto-TCAS, auto depressurization descent, and landing distance monitoring, that aren't available on older models. These enhance safety.

Certainly certification and crashworthiness standards have improved over time. For example, 16 G crashworthy seats were introduced in 1988. Improved access to exits and fire resistant materials were other requirements phased in by the FAA.

And finally, the FAA now has the position that you cannot maintain an aircraft safely forever, with regulations called the Limits of Validity. As an aircraft ages, the structure incurs fatigue damage. At one point, the damage will be so prevalent, that cracks will merge and you'll have an Aloha 737 accident.

Concerns that such damage will be missed or occur in areas that cannot be inspected have led to the LOV, which is an upper flight cycle/flight hour limit at which the aircraft must be scrapped. Notably, this was something that Soviet/CIS certified aircraft always had.

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    $\begingroup$ Thank you for your answer but it seems a little off the point. When I compared older aircraft to new aircraft, what I meant was a comparison between older aircraft versus newer aircraft in age, not one between aircraft in different generations with different technology, for example between 20-year-old B737NG and and brand-new B737NG, not between B767 and A350. $\endgroup$
    – lemonincider
    Jan 26, 2019 at 10:08
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    $\begingroup$ @lemonincider "not one between aircraft in different generations with different technology, for example between 20-year-old B737NG and brand-new B737NG" A 20-year-old B737NG and a brand-new B737NG also have different technologies. $\endgroup$
    – DeepSpace
    Jan 27, 2019 at 17:13
  • $\begingroup$ seems Airbus has removed that document as I'm unable to see/download it :( $\endgroup$
    – shirish
    Sep 3, 2021 at 18:22
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Just from the factory new may not be the best. Many electronic devices (and there are lots of them in a modern airliner) have the short "burn in" period when they fail more often, here and more realistic plots here. Then there is a long service period when they are reliable, and ultimately the reliability degrades again as the device gets old and should be replaced.

I would probably pick an airliner that have already flown few hundreds of hours.

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