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Jet engines are tested for this.

They basically can shoot (not only throwing!) entire frozen chicken cadavers into engines with zero damage.

The only way they managed break the entire engine was to place little explosives on the turbine wings. Even that didn't cause a fatal disintegration of the jet engine.

Somewhere on YT there's a super entertaining video from a test facility.


Well first, the linked article was regarding a weather balloon that impacted the windscreen, not the engine, and it did cause an injury to the flight crew. Here are pictures of the bloody, glass-shard filled flight deck. https://www.facebook.com/aviation247/posts/n17327-united-air... So the hazard is real.

Now back to your uninformed comment. I do certification testing of jet engines, and we most certainly DO NOT test jet engines against the ingestion of airborne electronics.

I have personally loaded and fired the five barrel bird gun at General Electric’s Peebles Test operation many times over the years. We use a range of birds and bird simulators, but none of them are ever chickens, and none of them are frozen.

There is not any requirement for zero engine damage. Little sparrows will do no damage. Ducks and geese cause extensive damage every single time. Extensive engine damage is permitted so long that the engine shuts down without causing catastrophic damage to the airframe. The specific damage that must be prevented, per 14 cfr 33.75, is below. Any other damage is acceptable.

(i) Non-containment of high-energy debris;

(ii) Concentration of toxic products in the engine bleed air intended for the cabin sufficient to incapacitate crew or passengers;

(iii) Significant thrust in the opposite direction to that commanded by the pilot;

(iv) Uncontrolled fire;

(v) Failure of the engine mount system leading to inadvertent engine separation;

(vi) Release of the propeller by the engine, if applicable; and

(vii) Complete inability to shut the engine down.

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-C...


Thanks for the very informative post on airline engine testing. One of the quickest upvotes ever. Never knew the details on the range of birds fired and actual damage allowables.

Couple follow on questions. What are the test conditions like? Is the test basically a static air test with a fixed engine and a 500 mph duck / goose carcass striking an operating engine? Or do they put it in a wind tunnel to simulate high speed wind forces also?

Also, what's the method of actually firing and accelerating a duck / goose carcass up to airline speeds for impact. Did this a bit for NASA impact testing, and we tended to use peel away sabot rounds to throw bricks at objects.

Also, borders a bit on a Monty Python joke, yet is there a regulation duck / goose? They can vary pretty wildly in size / weight. 5lb, 10lb, 20lb? Are they firing all the way up airline cruise speeds (500-600 mph? or just take off / landing runway issues?

Finally, being in the industry, any idea on what's been going on with the engines peeling off airplane wings, like that Louisville, Kentucky cargo plane? That seems like a rather drastic failure mode, since apparently there were cracks in the mounting and people just weren't checking?


FAA explicitly requires birds used in strike tests NOT be frozen, because frozen birds do not realistically simulate real bird strikes.

https://en.wikipedia.org/wiki/Chicken_gun


There are thousands of weather balloon starts every day without any damages to airplanes.

It's not factor as long they are not crossing a specific size/weight - jet engines and windows from airplanes are tested to withstand a direct impact.


Yeah, and pico baloons are extremely tiny, often at 10 grams or less, comprising some very thin plastic, some thin wire and tiny PCBs - this is also how they can fly so high for so long.

Lost of types of hail will be much heavier and harder on impact for example.


https://eur-lex.europa.eu/eli/dir/2009/24/oj/eng

Directive 2009/24/EC, Article 5 + Article 6

Under special circumstances it's legal within the EU do do this.

And removing a freaking old copy protection dongle to allow emulation of the software you legally are allowed to use falls under this.


These numbers are far off reality.

80k€+ isn't a high salary for job in a Tarifunternehmen if you stay with it for 5+ years.

Many of my colleagues cracked 100k€ this year without being AT and having crazy high position ratings.


> Many of my colleagues cracked 100k€ this year without being AT and having crazy high position ratings.

And for each of those guys there's 2 people working for 48k and happy about it. They've been at the same shop for 15 years, in a team of the only 3 people doing software in the entire company. Probably somewhere a bit rural, and/or north of Frankfurt.

IGM is not the default.


Let me guess: They are working in one of the IGM-connected companies?

I don't trust these numbers for Germany.

Why? Have a look at all the Tarifunternehmen salaries. 80k-90k€ is pretty much a standard salary you can reach after 5 years (with maybe changing your position once within the same company).

Feels like their dataset has significant sampling gap in some very big industries here.


It doesn’t matter honestly, 65k versus 80k after 42% tax on the extra 15k is about 800 euros a month. Not qualitatively different.

€65k is $77k is £56k. Takehome is 61% Germany, 76% UK, 77% US

€80k is $94k is £69k. Takehome is 60% Germany, 73% UK, 75% US

If Germany taxed at US rates at €65k it would be an extra €867 a month, "Not qualitatively different"

When US IT jobs are on twice the salary ($150-200k or €130-160k) that's a hell of a lot bigger impact than the tax.

US https://smartasset.com/taxes/california-tax-calculator

UK https://listentotaxman.com/

Germany https://www.how-to-germany.com/income-tax-calculator/


Reality is ~36-38% if you learn to spend money strategically so you can fill a proper tax return.

I never paid 42% my entire engineer life.


OK that's an extra €20 a week, doesn't really change the point

What are you doing, for the non-Germans? I'm wondering how onerous your tax optimization strategy is.

There are many tools available in Germany that support you doing your tax filings. They have endless questionnaires in (tax law free) easy language that guide you through all the taxing niches. They not only respect all rules regarding the laws but also the latest jurisprudence.

Like: If you have a lockable, separate office and work (almost) exclusively from home, you can basically deduct the entire room for tax purposes (rent + electricity + heating + insurance + etc).

That can make a huge chunk.


....but wait until Finanzamt comes along and measures the size and checks with a controller if this room is really ONLY for work - if there is the slightest sign that this room maybe used for other things, your plan is gone.

Even an additional single sofa/couch can crush this plan.

And: If you say the room is worth 500€, you dont get back this 500€ with yearly tax declaration - you only get this amount deducted from total income, rising your after-tax income a little bit. In fact, with this solution you loose a room PLUS some money - rather rent out the room 1 week per AirBnB and pocket this in cash and you are fine.

Source: I was once hit by them with these rules.


> 800 euros a month. Not qualitatively different.

Put 800 euro a month into an investment account and you’re a millionaire by age 50.


Compound interest is a think but we wont be millionaires by age 50, especially in modern times where people study long and start working in their 30s.

Very few companies pay the union salary.

Meshcore and -tastic have the huge problem that the encryption keys are bound to the device and not the app.


I've been using the T-Deck Pro and T-Lora Pager, so the device is the app.


I agree, there's way too much going on in the firmware, just make a dumb Lora-bluetooth bridge. Hell, just integrate a Lora radio in a phone.


The base software is open, you could potentially do it!

:)


Honestly: MC and MT are classical bloated Arduino projects with a giant single big-loop and an interrupt coming from the LoRa modem.

Both projects are hitting their limits because of this. Every new feature and every bug fix causes endless amount of pain and breakage.

I was involved in both - and gave up because of this.

IMHO both projects need some kind of thin-client which delegates most of the functionality into the client. Only keep some basic LoRa/Message Buffer/Routing/Battery Saving functionality in the hardware itself.


ECMWF is the best which is available globally.

But often there are local models with are better for specific regions.


You can see the most important charts from the ECMWF model for free on ecmwf.int. But you will not get the data behind them.


> Hiking has the biggest effect though.

Keeping the mind busy with beautiful things and being physically exhausted can heal a lot of things.

Its like surfing on a big day - you are just too tired to be depressive afterwards. It feels like a weight blanket.


It's also endorphins. Natural drugs.

I don't have the energy to do all that when I'm down though. I hate all sports though I do like hiking (there's no team or competitive bullshit) but I'm too clumsy for it.


Europe was always great in weather/earth observation from space.

Their stuff basically works 24/7/365 without causing much noise. With fully automated data intake processes.


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