# Has any UFOlogist managed to explain the crash rate of these UFOs?

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#### Deleted member 19405

##### Guest
I mean, we fly tens of thousands of aircraft every single day with barely any crashes per year, so for these UFOs to crash as much as they seem to be
- remember, we have at least a dozen of "confirmed" crashed alien craft and counting - they'd have to be sending them over at a relatively high rate if the tech is comparable (which I cannot see how it could be).

I have done some basic research and ran the calculation through ChatGPT with the following prompt:

I'd like to compare the crash rate of human vs alien aircraft.

Let's imagine we know that at least 12 alien aircraft have crashed on Earth in the course of its 4.5 billion years history. We also know that according to the Aviation Safety Network, as of 2021, there have been over 156000 recorded plane crashes since the invention of powered flight. We also know that roughly 100000 flights take off and land every day all over the globe.

Calculate how many alien aircraft would have to have visited Earth to achieve the same crash rate as that of human aircraft.

To calculate the number of alien aircraft that would need to have visited Earth to achieve the same crash rate as human aircraft, we can use the known crash rate of human aircraft and the information provided.

Given that there have been over 156,000 recorded plane crashes since the invention of powered flight, and roughly 100,000 flights take off and land every day, we can calculate the average daily crash rate of human aircraft:

Average daily crash rate of human aircraft = Total crashes / Total days of powered flight

Assuming an average of 365 days in a year, we can calculate the average yearly crash rate of human aircraft:

Average yearly crash rate of human aircraft = Average daily crash rate of human aircraft * 365

Let's calculate this:

Average daily crash rate of human aircraft = 156,000 / (100,000 * 365) = 0.00427

Average yearly crash rate of human aircraft = 0.00427 * 365 = 1.55755

Now, we can calculate the number of alien aircraft that would need to have visited Earth to achieve the same crash rate:

Number of alien aircraft = (Number of human crashes / Average yearly crash rate of human aircraft) - 12

Number of alien aircraft = (156,000 / 1.55755) - 12 = 99,966.45

Therefore, approximately 99,966 alien aircraft would need to have visited Earth to achieve the same crash rate as that of human aircraft, assuming the information provided is accurate.

I am really bad at math so can someone maybe check if the calculation is correct or if some of my assumptions are really inaccurate? Thanks!

I am really bad at math so can someone maybe check if the calculation is correct or if some of my assumptions are really inaccurate?

Article:
As a total of 652 people have flown into space under the USAF definition, and 19 of them have died, so the current statistical fatality rate is 2.3 percent.
With that rate, 521 UFOs never crashed.

Article:
In 2019, there were 21 helicopter accidents per 100,000 flight hours in general aviation.

With that rate, 12 alien crashes correspond to 57,000 UFO flight hours.

Article:
The fatal accident rate in 2019 for general aviation was 1.029 fatal accidents per 100,000 flight hours.
With that rate, we'd be looking at 12 million UFO flight hours.

Commercial aviation is even safer.

I've since realized it's pretty much useless for these sorts of calculations. So I've re-done them manually as follows. I've also realized it's kind of meaningless to bring the difference between the individual time frames (100 years vs 4.5 billion years) into the calculation if all I'm after is the actual crash rate per se.

So, according to the web site linked in my OP we have recorded circa 100,000 flights per day in recent history, which as someone has correctly point out to me is a number that has possibly grown exponentially over a period of the 120 years of powerd flight. What would be the total number of flights humans have performed in their aircraft over that period? My gut tells me it would be maybe 10,000 daily flights x 365 days x 120 years = 438,000,000 total flights. Let's work with 450 million to account for some unrecorded flights.

Out of this 450mil flights, there have been 156,000 recorded crashes (again, accordin to a Quora AI bot answer, so I cannot vouch) which constitues a 0.035% crash rate for human aircraft. BTW that's a damn fine and commendable crash rate for a race that's barely made it to the Moon, if you ask me.

Now let's look at the aliens. Let's say 12 alien craft have crashed on Earth. To get a similarly commendable crash rate of 0.035%, there would have to have been circa 35,000 alien flights total. BTW if only 4 have crashed, that number decreases to 11,500. If only one has crashed, the total number of alien flights would need to be 2,900. But let's work with the mean which is 16,500.

These numbers would then double with each doubling of the assumed "safety" of the alien craft inferred from their comparative tech advantage vs. humans. In other words (sorry I'm not a native speaker), if the aliens are twice as technologically advanced as humans, their craft would be twice as safe and thus would crash only 0.017% of the time. But this would then require them to fly not 16,500 flights here, but 33,000. Etc.

Does this calculation seem more reasonable? Thanks!

So, according to the web site linked in my OP we have recorded circa 100,000 flights per day in recent history,
Commercial flights. That's the safest category of flights.

The more flights there are, the safer they become.

If you try to trace the first 12 crashes in aviation, you might find a very small number of successful flights to go along with them. The spacecraft accident figure in my post reflects this. Extraterrestrials wouldn't have much experience designing interstellar craft, or craft suitable for other planets, at first, with correspondingly high accident rates.

That's why it's my conviction that extraterrestrial craft would aim for Earth orbit.

We have to assume that these Aliens don't recover their own crash victims, or take steps to recover vehicles so as not to violate the Prime Directive.

Didn't you guys know about the big recall of the EONIX-15 gravity baffles? They always were a bit twitchy. That explains most of the "incidents" right there.

That and the fact that probably 99%, if not 100%, of any crashed vehicles are just fables.

I'd argue a much better analogy for the supposed situation would be space probes. After all, these craft are supposedly being sent from distant places to perhaps unexplored planets from their makers' point of view. As we saw from Russia recently, crashes of remote probes are very common. According to this Wired article from 2012, 70% of Mars landers crash. https://www.wired.com/2012/08/failure-to-reach-mars/

If the claims of alien "crashes" were limited to small uncrewed probes that would be one thing. But don't most of the stories claim that these were crewed spacecraft or that bodies or biological materials were recovered?
Humans have in fact sent out numerous space probes that are not designed to land on any body and during the first decades of space exploration it was not uncommon for them crash during the mission as designed. Obviously, putting people on board changed the design parameters a bit.

I'd argue a much better analogy for the supposed situation would be space probes. After all, these craft are supposedly being sent from distant places to perhaps unexplored planets from their makers' point of view. As we saw from Russia recently, crashes of remote probes are very common. According to this Wired article from 2012, 70% of Mars landers crash.
Not sure that's a better analogy. 100% of our craft are galactic (as opposed to intergalactic) and cannot achieve FTL travel or space-time-warping or anti-gravity any other physic-defying behavior as NHI craft allegedly can and do. Comparing our cutting-edge tech with what must be extremely simple tech for NHIs with these alleged capabilities doesn't seem appropriate. Comparing to our well-understood, commonly tech seems appropriate.

As Arthur C. Clark wrote:

### “Any sufficiently advanced technology is indistinguishable from magic.”​

If any interstellar traveling aliens ever show up, you can be sure they have "sufficiently advanced technology".

People don't like to think that somehow humans are not, in the end, the bestest/smartest critters in the universe. So if our aircraft crash the aliens equivalent must crash too.

Maybe Earth is to intergalactic civilisations what Gander is to us: mostly uninteresting, but a good place to divert to when your craft develops problems crossing the intergalactic ocean (at least we have restaurants). This means that Earth self-selects for malfunctioning extraterrestrial craft, which explains the anomalously high crash rate.

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So if our aircraft crash the aliens equivalent must crash too.
But we "know" they do, and have done, ever since Roswell 1947 and Milano 1933 (assuming for a moment these are real).

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As Arthur C. Clark wrote:

### “Any sufficiently advanced technology is indistinguishable from magic.”​

If any interstellar traveling aliens ever show up, you can be sure they have "sufficiently advanced technology".

People don't like to think that somehow humans are not, in the end, the bestest/smartest critters in the universe. So if our aircraft crash the aliens equivalent must crash too.

When a Star Wars fanatic is told 'the TIE fighter screech crescendoing and waning as it flies past is unrealistic because there's no sound in space', he'll respond 'oh but their sound waves are advanced technology physics'.

The ufologist crash rate response is a classic case of a sci-fi storyteller patching up whatever unrealistic bits in the story are pointed out by the viewers.

Arguing with storytellers about their story is the first mistake. You'll always get a plot-twist as a response that fits the main narrative and satisfies the enthusiast.

If the claims of alien "crashes" were limited to small uncrewed probes that would be one thing. But don't most of the stories claim that these were crewed spacecraft or that bodies or biological materials were recovered?
Humans have in fact sent out numerous space probes that are not designed to land on any body and during the first decades of space exploration it was not uncommon for them crash during the mission as designed. Obviously, putting people on board changed the design parameters a bit.
Sure but according to some lore the "crew" are in fact expendable "biological robots". More generally, without knowing anything about the alien society and culture IMO it's really hard to use "aliens wouldn't crash!" as a counterargument -- the craft may even be explicitly designed to crash, like our unmanned probes often are after their useful life is expired.

Out of this 450mil flights, there have been 156,000 recorded crashes (again, accordin to a Quora AI bot answer, so I cannot vouch) which constitues a 0.035% crash rate for human aircraft.

No....it doesn't. You are comparing apples and oranges. A single plane can fly many 'flights'.....but a single plane ( generally ) only crashes once. That is extremely relevant if we are looking at how reliable alien craft are compared with human ones. We need to know how many craft have taken part in all these flights.

For example, the aliens may have 10 extremely reliable craft where each one flies a million missions on average before crashing. Or they may have a million really rather unreliable craft where each one flies 10 missions before crashing. The result on Earth will be 10 million UFO sightings and 10 UFO crashes either way. With the extremely reliable ones that would be their entire stock....but they would still be vastly more reliable.

Who says being good at interstellar travel makes you good at navigating within an alien atmosphere? For all we know, the latter is more difficult even when the former has been sorted out. On the other hand, who says they aren't losing craft in interstellar flight as well?

I tell you what though, if I were worried about counter intelligence, I'd make sure I wasn't sending my best stuff to go check out an alien world. How could I predict which ways they might use it against me?

Who says being good at interstellar travel makes you good at navigating within an alien atmosphere? For all we know, the latter is more difficult even when the former has been sorted out. On the other hand, who says they aren't losing craft in interstellar flight as well?

I tell you what though, if I were worried about counter intelligence, I'd make sure I wasn't sending my best stuff to go check out an alien world. How could I predict which ways they might use it against me?
If that was actually a concern they'd have plenty of options:
1. Never enter the atmosphere, just do a fly-by
2. Include a self destruct device
3. Come in fast enough to leave nothing by a crater

The level of "crash" described by UFO-ologists would be more akin to a bad landing by our aircraft with rather a lot of intact parts claimed as evidence (despite no one actually seeing it first hand.)

For example, the aliens may have 10 extremely reliable craft where each one flies a million missions on average before crashing. Or they may have a million really rather unreliable craft where each one flies 10 missions before crashing. The result on Earth will be 10 million UFO sightings and 10 UFO crashes either way.
Check your maths. The million unreliable craft result in a million crashes for 10 million flights.

I could be casually referred to as a "ufologist" and I can explain the crash rate.
But...I also realise that I am an outlier amongst "ufologists".
The Ufo (non prosaic)crash rate = zero
The Ufo Mythos crash rate is more than zero...its a fluid number always rising..
Most ufologists cannot understand that the more "crashes" reported, lowers the probability of any crashes being legit(non prosaic)..they think its the reverse..
My ufologist friends are stunned when I tell them the crash claims are pure garbage..

I'm not a ufologist but I can try: Assuming these crashes are real I can think of several explanations:

1. They're running experiments , the aliens didn't actually crash their flying saucers because they were incompetent, they just pretend to crash them, leave some debris in the desert and see what the humans would do. We do the same when studying animals, there are many animal studies where we leave food, tools, etc around just to see what they'll do.

2. Genuinely crappy spacecraft: it might simply be more economical to build crappy spacecrafts, our own economy and body follows this philosophy. our cells are constantly dying and newing, and instead of building everything to last for centuries, we generally choose to build things that only last a few years and replace them when they break.

If aliens obey the laws of special relativity, one possibility is that they might travel by accelerating a very small amount of mass, mostly redundant information storage and some really microscopic manufacturing tech to high speed, And once they arrive at the destination, they'll build new aliens bodies and space ships at the destination.

That's how we travel in the long term, when we colonize a new area we don't bring everything with us, we make human babies, and ships, and houses out of local materials and in the process we adopt to local conditions. This might also explain why supposed aliens look like us: they didn't come from very far away, they were build right here on earth based on the a successful local design.

3. The stuff that crashed are not spacecrafts, but garbage / waste / broken parts. When humans travel, we leave tons of debris too. Mt Everest is basically one giant garbage dump. Human spacecrafts produce tons of space garbage. Even successful human space missions often involve a lot of spaceship parts crashing.

4. Internal conflicts. Slaves something rebel and burn their ships and die with their captors, people sometimes commit suicide by driving an airplane into the ground. Aliens could quite possibly do the same out of social or psychological reasons that make sense for them.

The problem with "believing" and "debunking" is that anyone can come up with dozens of explanation for anything. in fact some philosopher of science maintains that any theory can be kept consistent with the data if you just posit more and more factors.

I'm not a ufologist but I can try: Assuming these crashes are real I can think of several explanations:

All of these are plausible hypotheticals but the yardstick you are using for these hypotheticals is human reasoning. We do x so another alien species may also do x. If a highly advanced species exists they may have a completely different spectrum of thought and their motivations may be completely dissimilar to ours.

Without evidence, the number of possibilities is endless.

• the crashed spacecraft contained nanomachines, and their only purpose was to release them into our environment

• the crashed spacecraft are unmanned interstellar probes accidentally caught by gravity, they were never meant to be capable of atmospheric flight

• the "spacecraft" are really non-organic beings who come to Earth to die, attracted by our electromagnetic emissions

and if one of my last suggestions is true, we shouldn't be looking at the rate of crashed aircraft, but rather at the rate of beached whales

• Earth's EMF emissions far exceed intergalactic safety standards and burn out the navigation equipment of spacecraft. An interstellar task force is underway to put Earth in "airplane mode".

• The solar system is an intergalactic nature reserve, and cloaked Federation rangers bring down illegal intruders/poachers.

• The solar system has accidentally floated into a lane of a hypergalactic bypass; spacecraft crash into us because they don't expect us to be there.

• aliens are illegally dumping their wrecked craft on Earth instead of disposing of them properly (but expensively)

• intergalactic insurance fraud, because Earth is inhabited, the investigators are prevented from examining the wrecks

• like OceanGate's Titan, the pressure got to them, for much the same reason

• aliens like to play an intergalactic game of snooker, and Earth is one of the pockets

Without evidence, the number of possibilities is endless.

• the crashed spacecraft contained nonmachines, and their only purpose was to release them into our environment

• the crashed spacecraft are unmanned interstellar probes accidentally caught by gravity, they were never meant to be capable of atmospheric flight

• the "spacecraft" are really non-organic beings who come to Earth to die, attracted by our electromagnetic emissions

and if one of my last suggestions is true, we shouldn't be looking at the rate of crashed aircraft, but rather at the rate of beached whales

• Earth's EMF emissions far exceed intergalactic safety standards and burn out the navigation equipment of spacecraft. An interstellar task force is underway to put Earth in "airplane mode".

• The solar system is an intergalactic nature reserve, and cloaked Federation rangers bring down illegal intruders/poachers.

• The solar system has accidentally floated into a lane of a hypergalactic bypass; spacecraft crash into us because they don't expect us to be there.

• aliens are illegally dumping their wrecked craft on Earth instead of disposing of them properly (but expensively)

• intergalactic insurance fraud, because Earth is inhabited, the investigators are prevented from examining the wrecks

• like OceanGate's Titan, the pressure got to them, for much the same reason

• aliens like to play an intergalactic game of snooker, and Earth is one of the pockets

LOL, this reminds me of:

Check your maths. The million unreliable craft result in a million crashes for 10 million flights.

Yes but it doesn't invalidate the accompanying point that a plane can fly many flights but crashes only once. Going back to the original example that I disputed...if there have been 450 million flights and '156,000 crashes' then I dispute that the 'crash rate' is 0.035%. What actually matters is how many planes were involved.

Actually, the 156,000 crashes appears to be wrong......it had better be, as it would seem that only around 150,000 planes have ever been built....

https://www.telegraph.co.uk/travel/...iation enthusiast,been been more than 150,000.

According to Wikipedia the total number of aircraft incidents since 1970 is 11,164

https://en.wikipedia.org/wiki/Aviat...tal fatalities due to,226 as recently as 1998.

That would mean that around 7% of aircraft have crashed at some point. Sure, on average each one did 40,000 flights before doing so. But the point of relevance to UFOs is that we ( supposedly ) only ever get to retrieve the crashed ones....the 7% of all UFOs ever built. This is why the UFOs would seem 'unreliable'....because we don't get to see the number of flights before crashing. Just the crashes.

This post has quite a lot wrong with it (sorry).
Yes but it doesn't invalidate the accompanying point that a plane can fly many flights but crashes only once. Going back to the original example that I disputed...if there have been 450 million flights and '156,000 crashes' then I dispute that the 'crash rate' is 0.035%. What actually matters is how many planes were involved.
• It's the crash rate per flight
• we're trying to relate UFO sightings and crashes
• so a crash rate per flight seems appropriate
my own post #2 uses crashes per flight hours
• any rate highly depends on which types of craft you look at
• and which years, the first 12 aviation crashes correspond to very few flights
Actually, the 156,000 crashes appears to be wrong......
It probably is, as it's a chatbot sourcing another chatbot.
I could not find an original source for this claim.
it had better be, as it would seem that only around 150,000 planes have ever been built....
That's demonstrably false.
Article:

That's over 250,000 units just off these 10 types. (The Il-2 had an average of 53 flights until loss, being a WW2 attack aircraft.)
This is sourced to airliners.net (probably the forum), where I couldn't find that estimate. Anyway, you wrote "around 150,000" when the claim is "more than", not "around".
Article:
The Bureau of Aircraft Accidents Archives (B3A),[52] formerly known as the Aircraft Crashes Record Office (ACRO), a non-government organization based in Geneva, Switzerland, compiles statistics on aviation accidents of aircraft capable of carrying more than six passengers, excluding helicopters, balloons, and combat aircraft. ACRO only considers crashes in which the aircraft has suffered such damage that it is removed from service, which will further reduce the statistics for incidents and fatalities compared to some other data. The total fatalities due to aviation accidents since 1970 is 83,772. The total number of incidents is 11,164.[53]

• best to source this to B3A/ACRO
• only passenger aircraft (>6 passengers)
• only total write-offs
• can't find the numbers on the referenced site, though summing the "statistics" for the years suggests it's correct for 2016
That would mean that around 7% of aircraft have crashed at some point.
• you're relating "aircraft ever built" and "crashes 1970-2016"
• omits all crashes before 1970
• compares statistics for different types of aircraft
Sure, on average each one did 40,000 flights before doing so. But the point of relevance to UFOs is that we ( supposedly ) only ever get to retrieve the crashed ones....the 7% of all UFOs ever built. This is why the UFOs would seem 'unreliable'....because we don't get to see the number of flights before crashing. Just the crashes.
the argument is that we do not have that many UFO sightings for each report of a crashed UFO, but that we should, if they're reliable.

From the OP:
approximately 99,966 alien aircraft would need to have visited Earth
But MUFON receives "500 to 1000 reports per month", and we were discussing MUFON case 115206 two years ago.

tl;dr it's easy to lie with statistics, especially if they're badly sourced and have different scopes (years, types of craft, etc.)

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Without evidence, the number of possibilities is endless.
• the aliens actually know far advanced tech, but construct their "contact craft" from retro tech as to not reveal their technological advantage to use, and to keep us from reverse-engineering their technology. But over time, they've lost the skills to employ these older technologies safely.

• It's the crash rate per flight
• we're trying to relate UFO sightings and crashes
• so a crash rate per flight seems appropriate

No.....I think the point I've been making has been missed.

Two groups each with 1000 identical cars may both have done 100,000 miles on average for each individual car. But cars in group A have all done 10 trips of 10,000 miles, and cars in group B have done 100 trips of 1,000 miles. If 100 cars from each group crashed...well group A will have 100 crashes from 1000 trips, but group B will have 100 crashes from 10,000 trips......in both cases the total average being 10 million miles.

So the 'crash rate per flight' is meaningless because some flights are 500 miles are some are 12,000 miles. Crash rate per distance flown is the one variable that does not change. The more utterly reliable we expect a vehicle to be, that is to say the longer the total distance flown before expiry, the closer we can approximate 'crash rate per vehicle' over its entire lifetime.

If you have lots and lots of average quality vehicles doing lots of flights then the sheer number of 'flights' distorts the picture and gives a false impression of reliability if the metric is 'crash rate per flight'.

https://www.safety.af.mil/Divisions/Aviation-Safety-Division/Aviation-Statistics/ I was curious if I could find any data on any type of crashes from the military so I was doing a little snooping.

This includes all classes of mishaps, ranging from minor incidents to major crashes (not courtroom accurate ):

In 2020, there were 109 aviation mishaps across all branches of the U.S. military.
In 2018, there were 111 aviation mishaps.
And 2016, there were 161 aviation crashes.

Smaller civilian aircraft in the USA:

2020: Preliminary data showed around 1,100 accidents.
2018: There were about 1,275 accidents.
2016: There were about 1,300 accidents.

I think the FAA says

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No.....I think the point I've been making has been missed.

So the 'crash rate per flight' is meaningless because some flights are 500 miles are some are 12,000 miles. Crash rate per distance flown is the one variable that does not change.
Have I missed the point? You cut your quote of my post right before this:
my own post #2 uses crashes per flight hours
And then there's this:
Article:
Approach and landing is the highest risk phase of flight, accounting for over 50 percent of all accidents at every level of aviation. Many types of accidents can happen during the approach and landing phase of flight.
You have one landing per flight, so a per-flight crash rate correctly models the risk for the majority of accidents. Your claim that "crash rate per distance flown is the one variable that does not change" is not supportable. (Even though you 'moved the goalposts'!)

Let's look at your example some more:
Two groups each with 1000 identical cars may both have done 100,000 miles on average for each individual car. But cars in group A have all done 10 trips of 10,000 miles, and cars in group B have done 100 trips of 1,000 miles. If 100 cars from each group crashed...well group A will have 100 crashes from 1000 trips, but group B will have 100 crashes from 10,000 trips......in both cases the total average being 10 million miles.
A "car spotter" on the highway at the town limits sign will see 10,000 trips and learn of 100 crashes for group A, but 100,000 trips and 100 crashes for group B. If you want to relate sightings and crashes, a "crashes per trip" statistic is meaningful.

Let's look at your example some more:

A "car spotter" on the highway at the town limits sign will see 10,000 trips and learn of 100 crashes for group A, but 100,000 trips and 100 crashes for group B. If you want to relate sightings and crashes, a "crashes per trip" statistic is meaningful.

This has no longer become analogous to our own data gathering - we've not attained "spotter" status. We'd see 200 crashes from 110,000 trips, and be none the wiser.

This has no longer become analogous to our own data gathering - we've not attained "spotter" status. We'd see 200 crashes from 110,000 trips, and be none the wiser.
That's the point, though: if we expect 0.2% crashes per sighting, then everything's fine; if we expect 0.035% crashes per sighting (as per @landout365 's second post), we have to wonder why we're spotting so few trips, or why there are so many crashes.

We definitely don't know how many miles these UFOs are travelling. If they're interstellar, their crashes/mile is going to beat all of our statistics even if every single UFO ever has crashed.

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That's the point, though: if we expect 0.2% crashes per sighting, then everything's fine; if we expect 0.035% crashes per sighting (as per @landout365 's second post), we have to wonder why we're spotting so few trips, or why there are so many crashes.

We definitely don't know how many miles these UFOs are travelling. If they're interstellar, their crashes/mile is going to beat all of our statistics even if every single UFO ever has crashed.
Per evidence - it's still 0/0.

Per evidence - it's still 0/0.
Yes.

The argument being made here is this:
* assume all UFO reports are true
* assume UFOs crash at a rate comparable to aircraft
* then, with 12 crashed craft (as per Grusch), we should have more UFO sightings

There's something wrong with each of these 3 steps, including the last one which underestimates both the number of UFO sightings and of aircraft crashes.

This has no longer become analogous to our own data gathering - we've not attained "spotter" status. We'd see 200 crashes from 110,000 trips, and be none the wiser.

My own point was that crashes per trip may be a meaningless figure for something we'd expect to be highly reliable. If a UFO crashes once in 1 million trips....we might think wow...that is ultra reliable. BUT...what if the aliens only have 1000 UFOs and between them they have done a billion trips, but we have 47 of them in a hangar somewhere. That would mean that getting on for 5% of all UFOs ever made would have crashed. Is that reliable ?

There's something wrong with each of these 3 steps, including the last one which underestimates both the number of UFO sightings and of aircraft crashes.

The thing that is wrong, as per my prior post just above, is that the 'crashes per trip' for UFOs may be be extremely low...maybe 1 in a million trips...but if the UFOs are making a vast number of trips and there are few of them...maybe only 1000 or so...then does our having ( allegedly ) 47 crashed examples mean they are reliable ? Somehow just 'crashes per trip' isn't enough. To me the real issue is...how many UFOs did the aliens make...and how many do we ( allegedly ) have in hangars. UFOs could be extremely reliable in terms of 'crashes per trip'....yet we might have 5% of all UFOs ever made in our hangars.

I think the point is that the two are not mutually exclusive.

My own point was that crashes per trip may be a meaningless figure for something we'd expect to be highly reliable. If a UFO crashes once in 1 million trips....we might think wow...that is ultra reliable. BUT...what if the aliens only have 1000 UFOs and between them they have done a billion trips, but we have 47 of them in a hangar somewhere. That would mean that getting on for 5% of all UFOs ever made would have crashed. Is that reliable ?
Yes, it's 20 times as reliable as "once in a million trips".

yet we might have 5% of all UFOs ever made in our hangars.
until you find UFOs with serial numbers, this speculation is baseless and useless

We definitely don't know how many miles these UFOs are travelling. If they're interstellar, their crashes/mile is going to beat all of our statistics even if every single UFO ever has crashed.

But that is precisely my point....which you then seem to disagree with. If we did have every single UFO ever made in a hangar somewhere, would they not then be un-reliable ? I mean, not every aircraft is in a crash. Not every Model T Ford broke down after 100 miles. There are even Trabants still going today. Yet we have the aliens entire stock of UFOs in a hangar, never mind that they can fly 100 light years, and they are reliable ?

You are agreeing in one breath and disagreeing in another.

My own point was that crashes per trip may be a meaningless figure for something we'd expect to be highly reliable.

My point is that you're debating how many fairies can safely ride on the back of a unicorn.

If we did have every single UFO ever made in a hangar somewhere, would they not then be un-reliable ?
No.