erroneous information found in SIM - Maybe

[Tuna-Salad 0]

Section 5 page 117.
"skydivers play a more integral role in aircraft operations than ordinary passengers, because their procedures can dramatically effect the controllability of the aircraft, particularly on exit"

Ok that part is fine.. now we go to part A just under..
"Parasitic drag reduces the airspeed necessary for flight and reduces effectiveness of control surfaces"

Feel free to correct me, but uh.. The more drag on an aircraft the more speed is needed to overcome that drag. So it should read..

"parasitic drag increases the airspeed necessary for flight......" Or because there is drag the airspeed needs to increase to sustain flight.

The way I read it.. it says the more drag you have the lower speed is needed to fly.

I understand what they are saying though -
Something small and I was sort of bored.

Millions of my potential children died on your daughters' face last night.

[quade 4]

A bit more wordy to be sure, but more accurately.

Quote

Jumpers positioning themselves outside the aircraft (aka floating) during jump run increase the parasitic drag of the aircraft which causes a decrease in flight speed which also reduces the effectiveness of the control surfaces.

Your statement, "parasitic drag increases the airspeed necessary for flight," is incorrect as drag opposes thrust. In other words, all the pilot need do to overcome the drag is increase power, but the airspeed itself can stay unchanged.

quade -
The World's Most Boring Skydiver

[Tuna-Salad 0]

That is sort of what I was driving at.. the more drag the higher the stall speed..

Millions of my potential children died on your daughters' face last night.

[quade 4]

The original sentence is ambiguously written to be sure and can be taken two ways depending on how one reads it.

It's a bit like the old SNL joke about;

"You can never put too much water into a nuclear reactor."

Does it mean that nothing bad will happen if you over fill it or does it mean that something horribly wrong will happen if you do?

quade -
The World's Most Boring Skydiver

[Tuna-Salad 0]

LoL

Millions of my potential children died on your daughters' face last night.

[CSpenceFLY 1]

"Parasitic drag reduces the airspeed , which is necessary for flight and reduces effectiveness of control surfaces"


Fixed it for you. Please send payment to CSpenceFLY at P.O. Box...

[DougH 270]

Quote

I understand what they are saying though -
Something small and I was sort of bored.

Lol. Then shut up and jump. Shesh.

"The restraining order says you're only allowed to touch me in freefall"
=P

[brettski74 0]

Quote

That is sort of what I was driving at.. the more drag the higher the stall speed..

This is not true. More or less drag does not have a direct relationship on stall speed. Case in point, extending flaps on the wing increases drag, but allows the aircraft to fly more slowly during takeoff and landing by lowering the stall speed of the wing. Conversely, spoilers also increase drag, but they interrupt the airflow over the top of the wing, killing the lift and increase the stall speed of the wing considerably.

The intended meaning of the author is as Spence noted above. Sticking objects, such as humans, on the outside of the plane increases drag. In the absence of any other factors, this will cause the plane to slow down, which in turn reduces the airflow over the control surfaces, which reduces their effectiveness.

[JohnMitchell 16]

Quote

The original sentence is ambiguously written to be sure and can be taken two ways depending on how one reads it.

It's a bit like the old SNL joke about;

"You can never put too much water into a nuclear reactor."

We actually watched that video at an FAA briefing on communication. Still a tag line in the control room.

[JohnMitchell 16]

Quote

That is sort of what I was driving at.. the more drag the higher the stall speed..

I think the stall speed would stay the same, since the weight remains the same. In fact, with the CG moving aft for exit as it does for most large aircraft, the stall speed might go down, since the wing loading would go down. However, the big warning is that all that extra drag and pitch up make it much easier to approach stall speed and maybe even stall.

[popsjumper 2]

Quote

Ok that part is fine.. now we go to part A just under..
"Parasitic drag reduces the airspeed necessary for flight and reduces effectiveness of control surfaces"

Feel free to correct me, but uh.. The more drag on an aircraft the more speed is needed to overcome that drag. So it should read..

You're introducing side issues into the statement.

The statement simply says drag reduces airspeed and that drag reduces control effectiveness. True.

It says nothing about having to counter the drag to maintain airspeed and control surface effectiveness.

The section is about how skydivers affect flight. It's not about what airplane pilots must do to counter those effects.

The good news is that your are reading, learning, asking and learning some more. Keep it up...for your entire skydiving career.

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

[docdialtone 0]

Parasitic? Now we're parasites? Thats it, I am never floating again!

[billvon 3,116]

>"Parasitic drag reduces the airspeed necessary for flight and reduces
>effectiveness of control surfaces"

In skydiving, that can be literally true. Lots of jumpers outside a King Air (for example) can reduce the effective airspeed over the tail and result in a reduction in pitch authority. Often pilots compensate by flying jumprun at a higher speed than would ordinarily be required for level flight. (They can also do other things like lowering flaps to change aircraft attitude.)