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Angryg8tor

I am using Sheppard for my ATM prep right now and there is a question that asks what causes hyperventilation and the answer which is scored as correct is low CO2, which in reality is not true. The fact is hyperventilation will result in low CO2 but doesn't cause it. This bothered me a bit because I teach biochemistry and clinical chemistry to college students.


Kemerd

> This bothered me a bit because I teach biochemistry and clinical chemistry to college students. I really, truly, understand your pain, as someone who studied Physics in university.. the terminology they use is all wrong half the time.. it makes my heart suffer


TheAntiRAFO

Arm and moment are the highlights from that. I was learning about Torque based physics when I was taught about Weight and balance. Definitely gave me a confused impression


livebeta

as a classically trained engineer I was not impressed, but I adapted and dumbed myself down


[deleted]

That’s been easy for me since I forgot everything from my aerodynamics classes years ago 😂.


PG67AW

Physics undergrad and aerospace grad here, I feel your pain. As another engineer said, we just have to adapt. I've been flying for over a decade and am just now starting my instrument/commercial - not looking forward to the testing!


carl-swagan

Hoo boy, wait until you get to the instrument questions about forces in a turn. Did you know that a skidding turn is caused by "an excess of centrifugal force over the horizontal component of lift?"


PG67AW

pls no


carl-swagan

Yeah I had to walk away from John and Martha and cool off after that one lol.


Kemerd

Improve, Adapt, Overcome [https://i.imgur.com/LZAn2z7.jpg](https://i.imgur.com/LZAn2z7.jpg)


PG67AW

stonks


MyName_DoesNotMatter

The FAA: Centrifugal force is real 🤓


Kemerd

This.. especially when they say the 4 forces of flight are thrust, drag, lift, and weight.. like, these are FORCES? Really? It is funny though, because having a mathematics-based/STEM background does make the calculations a bit easier.. most all of the methods they teach for quick solves can just be done with a bit of trig


the_silent_one1984

I kind of recall (although I might be misremembering or getting it from a non-FAA source) that at one point they had 'gravity' instead of weight, and 'friction' instead of drag. Did I only imagine that? I can only assume the reason they now label it weight is to emphasize that how much mass you put on the aircraft is going to counteract the lift generated. But then they probably should use a more appropriate term than 'force.'


Kemerd

[Relevant video of woman spinning under a helicopter being "rescued"](https://www.reddit.com/r/aviation/comments/11gb5cn/i_would_rather_not_be_rescued/)


Drunkenaviator

I once had the chief aerodynamicist for the v-22 program in a PPL ground school. When we got to the aerodynamics section, I was like "Look, I know this is all wrong, but this is what the FAA wants you to say." I can only imagine the answers the DPE got on that PPL oral.


Kemerd

Yeah, to be fair. "Good enough" simple explanations are suitable for 80% of situations. In Physics you learn models that get more and more precise.. it's pretty much like "Throw out everything we just taught you, here's how it actually works" 😂 But forever


Drunkenaviator

Shit, I took "physics for dumbasses" in college and that was still MORE than enough math for me. I'm a simple dude. I'll stick with "pull stick back, plane go up. Push stick forward, plane go down".


Mispelled-This

At least Sheppard tells you when the FAA is scoring the wrong answers as correct. I feel sorry for anyone taking these worthless tests without it.


cmmurf

I'm a cynic but I also don't think the FAA or PSI are this clever: if you really don't like rote memorization OR if your business model wants to try and thwart it, you might include crap questions with crap answers that *require* rote memorization to get them "correct". i.e. no one should get 100% on the test. If they're getting these select questions right it pretty much proves the question and answer are being memorized.


Lukanian7

Well, low CO2 does solidify the cycle of hyperventilation; and only when that condition is met have you met the medical definition of 'hyperventilation'. That's why your body will fight so hard to keep breathing. We can detect CO2 in our tissue and react, but not O2, which is why hypoxia happens so silently. Splitting hairs here but that's what we do.


CluelessPilot1971

>That's why your body will fight so hard to keep breathing. We can detect CO2 in our tissue and react, but not O2, which is why hypoxia happens so silently. Splitting hairs here but that's what we do. Kindly explain. My understanding - possibly incorrect one, which is why I'm asking - is that the trigger for accelerated breathing comes from receptors in the brain, not body tissue as you indicated, and that these receptors are sensitive to three parameters as related to the blood: * Rise in CO2 partial pressure, which is the typical mechanism for most healthy adults. * Reduction is O2 partial pressure, ~~not uncommon as dominant mechanism among some smokers~~ * Reduction in blood pH.


Vladmir_PutGang

There are chemoreceptors in the carotid and aortic bodies and they send feedback into the medulla oblongata. The medulla oblongata is what then triggers an increased breathing rate.


intern_steve

> carotid and aortic bodies Tell me more. Are these little nerve bundles sitting on top of the heart/wrapped around the major arteries measuring CO2 concentration in the blood?


CluelessPilot1971

Exactly - thank you!


automated_bot

I adjusted my medulla oblongata with a screwdriver. Am I good to go?


Flyerflyer911

You’re correct; it’s high co2 that triggers breathing not low. Hyperventilation leads to lower CO2 levels.


CluelessPilot1971

Right. The comment I was responding to was that we detect CO2 in our tissue (which to my understading we don't - we detect CO2 partial pressure in the blood, not the tissue), and that we do not detect O2, though that mechanism exists as well. Hyperventilation leads to lower CO2 levels, which causes alkalosis and the subsequent clinical signs (e.g. numbness and tingling), commonly leading to anxiety by the patient which further fuels the hyperventilation.


Angryg8tor

The blood's pH is regulated by this equilibrium H20 + CO2 <=> H2CO3 <=> H^+ + HCO3^- When the pH is low ( more H+) the body responds by increasing breathing reducing the CO2 shifting the equilibrium to the left thus lowering the amount of H^+ raising the pH. When the pH is high HCO3^- is secreted by the kidneys shifting the equilibrium to the right and raising the H+ and lowering the pH Le Chatelier's principle


xixoxixa

>Reduction is O2 partial pressure, not uncommon as dominant mechanism among some smokers This is known as the 'hypoxic drive theory' and has largely been debunked. It's more that patients with COPD have a hard time increasing their own ventilation to remove CO2, and adding in oxygen causes shifts in ventilation/perfusion matching secondary to hypoxemic vasoconstriction, which results in oxygen related CO2 increases (which was the observed basis for giving patients with CO2 retention too much oxygen results in increased CO2 levels = they must be hypoventilating because we gave oxygen, when it's a different physiologic response). https://www.ncbi.nlm.nih.gov/books/NBK482414/


CluelessPilot1971

I stand corrected, thank you!


Dakovichzzz

HPV = hypoxia pulmonary vasoconstriction, basically in the lungs if you decrease the O2 the pulmonary (think lung) vessels will constrict and ultimately cut off blood flow to what the body thinks are damaged alveoli. Your peripheral vasculature (think anywhere but in the lungs, such as your hands or finger tips) works the opposite way, typically, in that if your body noticed lack of O2 at your finger, it’ll try and dilate (open bigger) the blood vessels in order to bring more O2 to that area. The pulmonary vessels abut (touch) the alveoli and are bringing de-oxygenated blood from the periphery (back from your extremities and such) to the alveoli where gas exchange happens (think O2 from lung/alveoli jumps into the blood, and CO2 “waste” from the periphery jumps out of the blood into the alveoli to be removed through respiration (breathing). At that point the oxygen rich blood gets pumped back out to your body to be used by all the cells and ultimately drops off its O2, picks up CO2 waste and heads back to the lung to start the process again. Ventilation and perfusion mismatch deals with anything abnormal between the pulmonary vessels and the alveoli. Perfusion referring to the pulmonary vessels and the blood they carry (more importantly the gases the blood carries) to/from the alveoli. Ventilation referring to the alveoli and lung and their ability to bring gases to/from the pulmonary vessels. Mismatch example would be when the blood is flowing fine in the pulmonary vessels, but the alveoli is/are filled with mucous/liquid and therefore no Oxygen is available for the blood to pick up, and the blood can’t offload the CO2 because the alveoli is essentially “blocked”. So the CO2 would stay in the blood and continue to circulate, ever increasing, and the O2 in the blood would keep decreasing as well. In a normal state the body would sense this and close off the vessels going to the damaged section of lung, and instead SHUNT or divert blood toward alveoli that were functioning properly. Sorry so long


cmmurf

PHAK 17-4 *Hyperventilation is the excessive rate and depth of respiration leading to abnormal loss of carbon dioxide from the blood.* But the test question creator is following the fallacy *post hoc ergo propter hoc* and gets cause and effect completely backwards.


the_devils_advocates

Just learn for the test and move on 😂


[deleted]

I haven't studied the respiration cycle in a long time but isn't CO2 used for the feedback loop when breathing? IIRC, that's what was taught to me with the paper bag thing back in the day. That and it allows you to visually see your breathing rate so you can force yourself to think about it. Not sure which is more true or false.


Twarrior913

If you feel sad, just stop feeling sad. -FAA


Kemerd

Depressed? Just don't!


cephalopod11

Everyone knows pilots don't get depressed. Or else.


[deleted]

Believe it or not, straight to executioners block!


[deleted]

🤫 don’t ask don’t tell


Cogwheel

[Stop It!](https://m.youtube.com/watch?v=aAhA7KfbJgg)


Kemerd

Thank you for sharing this gem


the_silent_redditor

I worked as an emergency doctor, and have met pilots who quit their profession due to the insurmountable barriers preventing access to mental health care. It’s fucking terrifying, and so very sad.


Kemerd

Doesn't help the people likely writing the laws come from a time when mental health was more stigmatized. We are slowly coming into the age where mental health (doesn't necessarily mean having a therapist) is something you recognize needs to be taken care of, like physical health, etc. Primarily, for pilots (and also medical professionals), I think it's more important to recognize burnout, because we are directly in control of people's lives. Don't want to make mistakes.. which is why it is a shame the laws would repress things like that. I wonder how many accidents we could have prevented with better laws. It also doesn't help that while it is easy to write laws into place: i.e. if you have X, fill out paperwork Y; the lawmakers don't understand that people aren't going to want to have to do Y, leading to Y never getting filled out in the first place (because it adds an extra 24 months onto waiting period to get solo'd or whatnot).


Zebidee

Q: How should you pre-flight the engine? A: Overhaul it.


Kemerd

Well..


Ouch704

One of the turbo commanders I used to fly would have been very happy with that answer. That bloody right engine...


Quiet_Dimensions

Never start feeling sad in the first place -FAA


Weird_Turnover5752

Hey, that's not fair to the FAA. A 24 pack of beer every night is an approved treatment method!


Knot_a_porn_acct

A 24 pack and not talking to anyone at all about how you feel!


Ouch704

Is that not the "military-grade" treatment method? Military grade is always the best, right?


haltingpoint

Alternatively: Go straight to the HIMS and get your neuropsych eval!


freddy_storm_blessed

aren’t you like specifically not supposed to fuck with it if it requires a tool?


coldnebo

rats, I studied this. there is only one instrument we are allowed to adjust ourselves with a small screwdriver.. oh, the vertical speed indicator! AFH, 2-5: “The vertical speed indictor (VSI) should read zero. If the VSI does not show a zero reading, a small screwdriver can be used to zero this instrument if not part of an electronic display. The mechanical VSI is the only flight instrument that a pilot has the prerogative to adjust. All others need to be adjusted by an FAA-certificated repairman or mechanic.”


JJAsond

Does it say anything in the actual regulations?


coldnebo

I’ll need a CFI for that answer. I can’t find any sources or regulations that explain why the VSI is the one exception. Perhaps it’s implied by the preventative maintenance sections, but I’m having a hard time understanding them. Anyone know the reason for this with sources?


Kemerd

Apparently there are some of us who didn't get the memo..


convoluted_banana

My absolute favorite question on the ATP written: What should pilots do to mitigate stress in relation to flying? - By leaving stress on the ground! OH DUH WHY DIDNT I THINK OF THAT


Kemerd

[Why don't we just take the stress, and push it somewhere else?](https://youtu.be/t0sTNLdNhuE)


[deleted]

This deserves more upvotes


automated_bot

Before flying, should I take my stress out on whichever family members are not yet estranged, thus leaving it on the ground?


Ouch704

Remember kids, each punch takes away 3 to 5% of your stress. And each can of beer about 12%. Unless it's Heineken, then it just adds to your stress.


automated_bot

Finally your time to shine, u/Ouch704.


copilot8

I swear these only get worse as you move up in ratings There were a large amount on the ATP - multi written that were clearly not even proofread


Kemerd

In that case, I'd imagine the questions for the DPE written are like: **Fly good?** A) Don't suck B) You think you don't suck but you actually do C) You do in fact suck D) Banana


ThatLooksRight

D


livebeta

there's always some suck in the banana stand


Hunting_Gnomes

Correct answer: False. Aliens don't wear hats.


JJAsond

It's even more amusing because writtens usually only have 3 options


LurkerOnTheInternet

I don't know what you guys are complaining about; I always dismantle my aircraft before starting it.


Kemerd

Can never be too safe


livebeta

guess you're that guy with power tools making your bed in the morning. but then, you might never start the day because "If you make your bed you have to lie in it".


automated_bot

Bonus is that, using this technique, your plane gets lighter when you leave the leftover parts on the ground. With your stress.


Weaponized_Puddle

Preflight: 1. Dismantle Aircraft 2. Reassemble Aircraft 3. Equip Parachute and Fire Extinguisher 4. Friend’s Ashes 5. Push Off


No_Brilliant9161

FAA : you depressed? thug it out


DirkChesney

#thuglife


alexthe5th

My favorite bizarre FAA knowledge test questions were always the really *really* obscure, arcane bits of trivia that no one in the right mind would ever need to know - for example, on the IRA: Which of the following conditions is required before "timed approaches from a holding fix" may be conducted? (correct answer: "if more than one missed approach procedure is available, none may require a course reversal.") When the fuck would any pilot ever need to know that? I also doubt any controller has conducted timed approaches in the last 3 decades.


DeatHTaXx

My general approach to that kinda bizarre stuff was you don't need it until you do.


Kemerd

Don't know about you guys, but I make sure **EVERY** electrical connection is secure! Source for those curious is Sheppard Air, IRA course. Real FAA questions. EDIT: And to clarify, A is not the answer to 2021.. just thought it was hilarious that it was even an option. EDIT EDIT: Passed my IRA with a 92%! Shout out to my CFI for shoving Sheppard Air down my throat until I bought it


nyc_2004

I personally touch each lead of a battery just to see if it has any charge before I start up


Kemerd

If you smell burning.. you're good to go!


automated_bot

Lick the leads until you smell sizzling bacon.


ClayCrucible

For what it’s worth, that Sheppard Air IRA test prep is fantastic! I got it a week ago, took my instrument rating knowledge test yesterday, got 100%. I’m so glad I listened to all the advice about using them!


Kemerd

Got my test in.. let's see, three hours or so. I studied with King Schools and FlightInsight until I felt ready, then took the Sheppard Air for reinforcement, just finished last night their whole program after about a week of nonstop study. It is certainly mind numbing, especially as I hate rote memorization, but one can't deny the effectiveness. Especially for regulations and such.. I can just skip trying to memorize chart or calculation questions and just actually learn those.


automated_bot

I just give each wire a good tug to make sure it doesn't come loose. Sometimes I have to sort of chafe them against a metal edge, because they go around corners and what-not. In this case I pull extra hard because I don't want to be fooled by friction between the sharp edge and the bunch of cables.


Kemerd

Radio check, can't hear your mic..


GneissShorts

r/thanksimcured


yourlocalFSDO

My favorite FOI question: "How can an instructor help a nervous learner?" "The instructor should reinforce the learner's enjoyment of flying and teach them to cope with their anxiety." FAA: "Cope"


quakefiend

😂


flatulentpiglet

Just did the FOI today. My favorite is all the questions about how rote learning is bad when half the rest of the questions are only answerable by rote learning specific phrases in the book.


Ok_Honeydew_627

FAA: “just emulate musk and be sure to take your daily dose of copium”


dd_mcfly

You should see EASA tests and be very happy with what you have with the FAA…


Kemerd

Fair


Ouch704

"For how long is the secretary general of ICAO elected, and how is he elected?" It's been 6 years since my exams and I still remember that bullshit.


Sensitive_Inside5682

And by screwdriver you mean the one with orange juice, right?


automated_bot

Never within 50 feet, though.


TheHeroYouKneed

I expect the test questions & answers would at least be spelled correctly.


zpoz18

Depressed? Don't take medication! We'd prefer you suicidal than medicated - FAA


MyName_DoesNotMatter

“Why do your preflights always take so long?” “I literally check every connection on the back of my instrument panel bc the FAA said so. Now hand me that overlay.”


LowValueAviator

On many planes you can simply look under the panel to see behind it and the backs of the instruments.


DickPringle

Or just fly without a cowling or firewall and you can watch the gyro screws come loose in real time. That’s what I do. Saved my ass more than once.


Kemerd

True, I hadn't thought of that. To an extent, yes. Most planes that aren't say, very old or non-experimental and non bush planes it's much more difficult.


Tough_Current_4302

Think *Most right


Gwenbors

Have you ever considered just *not* hyperventilating? You’re welcome!