# All it needs is a treadmill... **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [August 2, 2013, 1:27pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149 "2013-08-02T13:27:24Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![LawMonkey](https://avatars.discourse-cdn.com/v4/letter/l/d6d6ee/32.png) [@LawMonkey](https://boards.straightdope.com/u/LawMonkey)\ **Post date:** [August 2, 2013, 1:27pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/1 "2013-08-02T13:27:24Z")
So I finally got over to xkcd’s what if page today, only to find that the question was “[What sort of rope would you need to tie a jet airliner down?](http://what-if.xkcd.com/56/)” I couldn’t help but thinking that this was eerily similar to a certain question we had around here one time. Unfortunately, he never addressed whether the plane, tied to the ground, would generate lift or not… ---
**Author:** ![FairyChatMom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fairychatmom/32/21906_2.png) [@FairyChatMom](https://boards.straightdope.com/u/FairyChatMom)\ **Post date:** [August 2, 2013, 1:53pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/2 "2013-08-02T13:53:15Z")
If it’s not moving, it can’t generate lift. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 2, 2013, 1:59pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/3 "2013-08-02T13:59:46Z")
Well, it’ll still generate some lift, from the air it’s moving across the wings, but on most planes that won’t be nearly enough. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [August 2, 2013, 2:02pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/4 "2013-08-02T14:02:53Z")
Curses, air foiled again. ---
**Author:** ![leftfield6](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leftfield6/32/18780_2.png) [@leftfield6](https://boards.straightdope.com/u/leftfield6)\ **Post date:** [August 2, 2013, 2:36pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/5 "2013-08-02T14:36:39Z")
Who would be on said treadmill, the plane or the whale? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 2, 2013, 4:18pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/6 "2013-08-02T16:18:08Z")
> [@FairyChatMom](#): > > If it’s not moving, it can’t generate lift. [![](https://img.youtube.com/vi/cHhZwvdRR5c/maxresdefault.jpg "Amazing video of 747 lifting in place in extreme wind conditions - 1080P HD") ](https://www.youtube.com/watch?v=cHhZwvdRR5c) ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [August 3, 2013, 6:51am UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/7 "2013-08-03T06:51:28Z")
> [@Chronos](#): > > Well, it’ll still generate some lift, from the air it’s moving across the wings, but on most planes that won’t be nearly enough. If said jet is tied down, what air is moving across the wings (unless it’s a very windy day)? Were you thinking of the air blown back over the wings by the propellers? Your typical jet-propelled airplanes don’t usually have a whole lot of propellers. ---
**Author:** ![FairyChatMom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fairychatmom/32/21906_2.png) [@FairyChatMom](https://boards.straightdope.com/u/FairyChatMom)\ **Post date:** [August 3, 2013, 1:01pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/8 "2013-08-03T13:01:14Z")
OK, let me rephrase my comment - if there’s not enough air moving across the wing, the wings can’t generate lift. Better? ---
**Author:** ![crowmanyclouds](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crowmanyclouds/32/19884_2.png) [@crowmanyclouds](https://boards.straightdope.com/u/crowmanyclouds)\ **Post date:** [August 3, 2013, 1:57pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/9 "2013-08-03T13:57:11Z")
> [@FairyChatMom](#): > > If it’s not moving, it can’t generate lift. > > > [@engineer\_comp\_geek](#): > > > > [http://www.youtube.com/watch?v=cHhZwvdRR5c](http://www.youtube.com/watch?v=cHhZwvdRR5c) Is that actually lift or just the wind pushing down on the horizontal stabilizer? > [@](#): > > … Without the weight of its engines and with its landing flaps deployed, the slightly tail heavy 747 … CMC fnord! ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [August 3, 2013, 7:49pm UTC](https://boards.straightdope.com/t/all-it-needs-is-a-treadmill/665149/10 "2013-08-03T19:49:05Z")
> [@Chronos](#): > > it’ll still generate some lift, from the air it’s moving across the wings… As Senegoid notes, the engines of most jet airliners move approximately zero air across the wings.