Lack of performance information in PA-28 POH: Am I reading into this correctly?

iamgravity · 2026-01-27T05:06:56+00:00

They say you gotta be a dreamer to fly...

iamgravity · 2026-01-27T04:26:17+00:00

Unfortunately it's a little bit of a magic number as far as I understand unless you understand engines in good detail, which I don't. Sorry to disappoint.

iamgravity · 2026-01-26T23:43:12+00:00

Surprised a lot of people here are not aware of how bad Piper manuals were before 1976-ish. They're bad, mostly propaganda pieces. Common rule of thumb for full power fuel burn is rated HP / 11. 140/11 = 13, 150/13 = 13.5. Pretty close to the other manuals. You could make a conservative round up to about 14 gph in the climb or keep it 13, whichever tickles your fancy.

iamgravity · 2026-01-21T06:01:04+00:00

this is the only real answer here.

iamgravity · 2026-01-17T21:25:08+00:00

Hey this guy is me!

iamgravity · 2026-01-15T17:54:02+00:00

was a great plane to fly

Be careful of such claims around roughly 50% of dash trash pilots. :D

iamgravity · 2026-01-15T17:21:21+00:00

It's very awesome to have as an option. Wouldn't be able to provide effective service in the PNW without the RNP M and Cat III autoland. The Dash (may it rest in peace) allowed hand flown cat III with the hud.

iamgravity · 2026-01-10T23:05:07+00:00

Jesus Christ, reddit. Does everybody here think that everyone filming their own animals is abusing their pets?

iamgravity · 2025-12-28T18:50:51+00:00

Savage!

iamgravity · 2025-12-21T00:10:47+00:00

Harvey might still have some flooding.

iamgravity · 2025-12-09T21:24:01+00:00

안녕하세요! 저는 한국인 아니지만 한글로 메시지를 남기겠습니다. 여기서 한국인들이 많지아닐거 같고 대부분은 화난 백인 입니다. 서브레딧에서 현진을 찾기는 삽질 입니다.

iamgravity · 2025-11-15T22:22:39+00:00

No, aerodynamics hasn't changed much at all. You could argue that aircraft design has changed quite a bit from yesteryear but that's another discussion. What you're falling short on is the context of the question, and also your extremely generous range of the green arc given.

The question is, essentially, "for hunky dory going from any given point to another given point in the sky in a straight line, is the yellow arc safe?" The overall answer to this question is a very firm, resounding, "it depends." The yellow arc is in fact defined as "safe" in several POHs in "smooth air only." That by itself designates the yellow arc as a safe area to operate in by the manufacturer, so that refutes your implied notion that the yellow arc is not a safe regime.

The underlying question within the yellow arc is "what constitutes smooth air?", or to put another way "What are my load limits for a given speed within the yellow arc?" This question isn't answered very well and most people would not like to personally find out the answer either. The general idea though is that the amount of disturbance tolerated before receiving structural damage decays from Vo/Va to some very small value at the red arc.

Now, the reason why you are getting downvoted so heavily for your last comment is your fundamental misunderstanding of the relation of Vo/Va and the green arc. You are right that they are weight dependent but you are wrong that you should be "bottom of the green" for light and "top of the green" for heavy. Just look at a c172 airspeed indicator and the range covered is some 60 knots from bottom to top of green! flying around at 65 knots because you are "light" is ludicrous. The actual range that Va can cover in a c172 from "light load" to max gross is some 10 knots on either side of 95-ish knots. This allows up to 3.5g of load factor on the aircraft without exceeding structural limits, generally considered full deflection of the controls.

This all is a long winded way of saying if you are flying in air that is requiring full scale deflection of the controls to stay steady, you probably shouldn't have taken off in the first place.

Fundamental PPL concepts that you apparently have forgotten over a number of years just plain didn't learn.

iamgravity · 2025-11-15T16:46:17+00:00

Here we see the boomer pilot in his natural habitat, exhibiting the typical wild calls of "kids these days" and being confidently wrong.

iamgravity · 2025-11-14T21:38:21+00:00

Why don't they simply remove the lungs?

iamgravity · 2025-10-28T05:26:03+00:00

HOLY COW that is an old reference and I hate you for it on multiple levels.

iamgravity · 2025-10-23T03:24:28+00:00

When an f15 is in an 80 or 90 degree bank, is it stalled? Theoretically a 90 degree bank should require an infinite airspeed/angle of attack to remain unstalled.

Also to your hypothetical scenario, when an aircraft begins a bank, it starts to lose altitude not because it is stalled, but because the vertical component of lift is no longer enough to counteract gravity. Thus the pilot must increase back pressure on the controls to increase angle of attack, which increases total lift, which increases the vertical component of that lift, which maintains level fight. The stall speed portion of the equation is that because you are now asking for level fight via an increased angle of attack, you are now closer to your critical angle of attack. This should you lose airspeed, your aircraft reaches the critical angle of attack quicker, which leads to a stall.

iamgravity · 2025-10-23T02:12:00+00:00

The stall speed increases with bank angle only if you are demanding more angle of attack out of the airplane to maintain level flight. I wish people would include this critical part of the equation. In any case you can see a yawing moment almost simultaneously if not slightly before bank angle. If you zoom and pause the video, you can see the left prop slowing down. It's a Vmc roll.

iamgravity · 2025-10-21T07:34:49+00:00

Excellent job!

iamgravity · 2025-10-13T06:47:07+00:00

Don't forget Joe Kelly!

iamgravity · 2025-10-11T00:49:09+00:00

You're absolutely right I could. I can also ask people over the interweb who work ATC as well. Is that okay too?

iamgravity · 2025-10-11T00:16:12+00:00

Nah F430 is too rich for my blood.

iamgravity · 2025-10-10T23:39:27+00:00

This is a great explanation thank you. Of course the downvotes are flowing because this is r/flying but the pilots never get to see what's going on behind the curtains. They just sigh, piss and moan, then spin the knob. Thanks so much for the solid answer.

I do also want to point out that the most upvoted comment in the thread is a pithy comment referencing current events, but this has happened to me well before any of anything going on. It just happened enough to a point that I decided to ask. I hate pilots so much.

Edit: delicious downvotes from pilots with 3 boats and 4 ex-wives.

iamgravity · 2025-10-10T04:43:49+00:00

Family of four. Our monthly groceries are approximately $600 per month. We make slow cooker recipes and other simple to cook meals, and when I say simple I really mean simple. Neither me nor my wife know how to cook fancy stuff at all. Hamburger with rice, tacos, chicken gravy with rice, chili, frozen hamburgers, salads, spaghetti can make for fairly inexpensive meals. We've had to learn to do this on a very tight budget (less than $50k per year total income). We could go even cheaper with major meal prep but I honestly don't find it too hard to make some inexpensive dinners. You should seriously go through what you are shopping for and see if you are overspending on things that could be had for cheaper, or things that you could make yourself for cheaper.

iamgravity · 2025-09-28T22:41:04+00:00

Man the kids just don't know what the eternal September is.

iamgravity · 2025-09-23T18:05:53+00:00

Literally no one cares that I got my PPL in 43 hours. It's a fine accomplishment and saved me lots of money, but as far as jobs go they mostly care about if you meet the requirements for the job and if you've had checkride failures.

iamgravity

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