Weta43 Posted July 10, 2006 Share Posted July 10, 2006 I was thinking about landings in LO & how generally it seems accepted that LO has pretty good SFM & very good AFM, but that landing is not the strong point of either – particularly the SFM. Given that ground effect only occurs close to the ground (Within ½ a wingspan of the ground ?) & that LO already continually calculates how far the planes are from the ground already – not least importantly for ground collision calculations – it seems to me that it wouldn’t be that great a step to modify the lift calculations so that as the aircraft passed within ½ a wingspan of the ground the lift generated was scaled up linearly to replicate this effect (if the height calculation was taken from the middle of the wings, the plane could still actually touch the ground, even with a linear calculation). Probably you would disable the effect at more than say ~ 20 degrees bank. I see three advantages to adding ground effect – not in any particular order they are: 1/ More realistic landings, both for AFM & SFM models. Perhaps even more noticeable for the SFM (which may have disappeared by the time E.D. could implement something) where at present you can just fly in at any old speed, bang her down & put the brakes on, but this would also add to the landings of the AFM planes (especially with randomly fluctuating wind gusts). 2/ Less hitting the ground when flying NOE – both in transit & during attack runs ground pounding. Real life aircraft to some extent create their own air cushion underneath themselves, which reduces the chances of their just dropping onto the ground at 1m/sec with a steady stick while flying over level ground. A bit of ground effect might also just make the difference between bottoming out with some part of the plane 5cm below ground and bottoming out 10cm above ground when trying to pull up after a ground attack run. 3/ I’m not so sure about this, but ground effect might help cover up some of the errors in the terrain mesh. At present there are quite a lot of places among the sides/tops of hills/mountains where the collision detection part of the terrain modeling doesn’t quite line up with the visual representation of the ground. The first thing the pilot knows about this is when their plane hits the mid air ridge. I’m not sure, but I guess that the ‘collision’ mesh is still actually contoured in these cases, in which case ground effect might help by giving the plane a little nudge away from the invisible ground - & in doing so also give the pilot a clue that they’re over dodgy ground & need to give it a bit more clearance. (I know this has been discussed before, but I think it's not a bad time for a reminder to E.D.) Cheers. Link to comment Share on other sites More sharing options...
Roman G Posted July 11, 2006 Share Posted July 11, 2006 Seems like a good idea to me! Link to comment Share on other sites More sharing options...
Mobius1 Posted July 11, 2006 Share Posted July 11, 2006 I would be all for anything that makes for more realistic landings. P.S. Ground effect takes effect within 1 full wingspan on the ground. Stupid thermals... Link to comment Share on other sites More sharing options...
LawnDart Posted July 11, 2006 Share Posted July 11, 2006 As long as we all agree that it's not "an invisible cushion of air"!:pilotfly: :megalol: LD [sigpic]http://www.virtualthunderbirds.com/Signatures/sig_LD.jpg[/sigpic] Virtual Thunderbirds, LLC | Sponsored by Thrustmaster Corsair 750D Case | Corsair RM850i PSU | ASUS ROG MAXIMUS X CODE | 32GB Corsair DDR4 3200 | Intel i7-8086K | Corsair Hydro H100i v2 Cooler | EVGA GTX 1080 Ti FTW | Oculus Rift | X-Fi Titanium Fatal1ty | Samsung SSD 970 EVO 1TB NVMe | Samsung SSD 850 EVO 1TB | WD Caviar Black 2 x 1TB | TM HOTAS Warthog | TM Pendular Rudder | TM MFD Cougar Pack | 40" LG 1080p LED | Win10 | Link to comment Share on other sites More sharing options...
Crusty Posted July 11, 2006 Share Posted July 11, 2006 As long as we all agree that it's not "an invisible cushion of air"!:pilotfly: :megalol: LD Whats wrong with that definition?...do you know how the effect is produced? oo err...missus:animals_bunny: ** Anti-Pastie** Link to comment Share on other sites More sharing options...
Sleek Posted July 11, 2006 Share Posted July 11, 2006 ok..hold tight and bear with me..this is what i know on ground effect. Ground Effect: If u were very slow and cautious in raising the collective,u may find that the helicopter slowly rises a short distance and to the hover a few feet off the ground without any change in the collective setting. If this happens,u can congratulate yourself on having demonstrated ground effect,riding on an air cusion produced by the rotor downwash. Ground effect magnifies the lifting power availiable for a given collective setting,but the effect falls off quite rapidly with height,and dissapears altogether at a height equal to the diameter of the rotor disc. Rough or sloping ground,violent manoevering or strong,gusty winds will all tend to spill the air cusion,push it off to one side,or prevent it forming in the first place,so a wise pilot is cautious about depending on ground effect for the lift needed to stay airbourne. In any case,for our first transition to forward flight we want to climb rather higher than this-say to a minimum of 100 ft/30mtrs. As u approach the desired height,ease the collective down slightly and weight to see the effect. Remember that a helicopter has momentum-the faster u were climbing (or descending),the longer it will take for your verticle speed to change till it actually reflects the new collective setting. As u lower the the collective,u'll also need to coordinate with pedal input. With practice,u can anticipate the effects of ur control input's..but be carefull in the early stages-it's hard to avoid over-correcting. Phew! sry bout the long post but i hope this helps some peeps to understand Ground effect in helicopters. p.s theres more to it..but i hope the kinda explaines Ground Effect. Weta (or mods) why not post this in the The Ka-50 Black Shark thread to keep all info in one place ;) Be Good..Be Strong..:drink: ;) Link to comment Share on other sites More sharing options...
Crusty Posted July 11, 2006 Share Posted July 11, 2006 good description..dont forget you have to factor in translational lift as well when doing a climbout or descent with any forward speed:) oo err...missus:animals_bunny: ** Anti-Pastie** Link to comment Share on other sites More sharing options...
Sleek Posted July 11, 2006 Share Posted July 11, 2006 cheer's..as i said above theres more to it..;) hopefully this gives some people an idea on what Ground Effect is..rdy for BS :) Translational lift btw is another subject ;) like these: Taking off and rising to the hover Ground effect (allready mentioned) Transition from the hover to forward flight Translational lift (allready mentioned) Climbing and diving Turning in forward flight Slowing to the hover from forward flight Landing problems and techniques Visibility factors Circuit pattern Final approach..the list goes on ;) Be Good..Be Strong..:drink: ;) Link to comment Share on other sites More sharing options...
Weta43 Posted July 11, 2006 Author Share Posted July 11, 2006 Hi, Partly I didn't post in the Ka-50 section 'cause 1/ I don't think there'll be time to implement this in LOBS (even though I suspect that as far as FM changes go this might be an easy one) & 2/ ground effect would be just a good effect to have in the fixed wing aircraft too (Maybe an AI Caspian sea monster :-) (JK) Maybe we need to get a wish list sticky again. Cheers. Link to comment Share on other sites More sharing options...
dynamocl Posted July 11, 2006 Share Posted July 11, 2006 Sleek, stop trying to pass on other peoples work as your own, its called plagerism. Firstly you can tell its not your work, because it is not how you normally post, the stolen text sticks out from the start and end of your posts. It is clear you changed a few words and grammer to make it look like yours. You stole it from the enemy engaged ground school documents. Look under ground effects here: http://www.razorworks.com/enemyengaged/usmanual/Chapter6.PDF Page 9. Nice try :) but in future, please reference where you copy your text from. Link to comment Share on other sites More sharing options...
Sleek Posted July 11, 2006 Share Posted July 11, 2006 listen... not once did i say it was my own work!,i said its what i know!!(after reading the EEAH manual yes) or do i wan't any praise so just chill out..and again like i said i hope it help's some people out. BTW if i knew there was a pdf doc do ya really think i would of sat here and typed all of that from the EEAH originall Manuall when i could of just posted a link like u did. Be Good..Be Strong..:drink: ;) Link to comment Share on other sites More sharing options...
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