dcs.sniper Posted July 4, 2018 Share Posted July 4, 2018 Hello, what are the parameters to fly a 2 point landing without bouncing? Do you have a video of a perfect 2 point landing to share? Thanks Link to comment Share on other sites More sharing options...
Frederf Posted July 4, 2018 Share Posted July 4, 2018 CG is aft of the wheels so any vertical velocity converts to a pitch up torque. Pitch up causes lift and thus the bounce. Avoid bounce by minimizing vertical velocity and adding forward stick input at the moment of wheel contact. This adds tail lift and arrests the pitch up. Link to comment Share on other sites More sharing options...
Captain Orso Posted July 4, 2018 Share Posted July 4, 2018 CG is aft of the wheels so any vertical velocity converts to a pitch up torque. Pitch up causes lift and thus the bounce. All true. Avoid bounce by minimizing vertical velocity and adding forward stick input at the moment of wheel contact. This adds tail lift and arrests the pitch up. This spells for disaster, because no one can react fast enough once the wheels touch the ground, before the tail is sinking, the nose starts to point upwards and you are ballooning. You have to recognize how close to the ground you are, and just before your wheels touch, slip the stick forward just enough so that your wheels make gentle contact, and hold the stick there--you can even add just a little more forward stick, but you really don't need to. This way, you are controlling when your wheels touch the ground, and not waiting to quickly react to their contact. When you hit the wrong button on take-off System Specs. Spoiler System board: MSI X670E ACE Memory: 64GB DDR5-6000 G.Skill Ripjaw System disk: Crucial P5 M.2 2TB CPU: AMD Ryzen 7 7800X3D PSU: Corsair HX1200 PSU Monitor: ASUS MG279Q, 27" CPU cooling: Noctua NH-D15S Graphics card: MSI RTX 3090Ti SuprimX VR: Oculus Rift CV1 Link to comment Share on other sites More sharing options...
Reflected Posted July 4, 2018 Share Posted July 4, 2018 I'm also struggling with this. They say the secret is to come in at a slightly higher speed, and then make a really low pass over the runway without wanting to touch down. Eventually you will, and that will be a nice gear landing, stick forward, keep the tail up. Easier said than done, though... Facebook Instagram YouTube Discord Link to comment Share on other sites More sharing options...
Captain Orso Posted July 4, 2018 Share Posted July 4, 2018 I found that before I had VR, it was exceedingly difficult to recognize just how close to the ground I was. Flying without is like trying to drive with your hand over one eye. I guess with enough practice, you can establish a visual recognition, but it's pretty awkward. When you hit the wrong button on take-off System Specs. Spoiler System board: MSI X670E ACE Memory: 64GB DDR5-6000 G.Skill Ripjaw System disk: Crucial P5 M.2 2TB CPU: AMD Ryzen 7 7800X3D PSU: Corsair HX1200 PSU Monitor: ASUS MG279Q, 27" CPU cooling: Noctua NH-D15S Graphics card: MSI RTX 3090Ti SuprimX VR: Oculus Rift CV1 Link to comment Share on other sites More sharing options...
Frederf Posted July 4, 2018 Share Posted July 4, 2018 At the moment of doesn't mean in reaction to. You're quite right that anticipating contact is better than reacting to it. Link to comment Share on other sites More sharing options...
dcs.sniper Posted July 5, 2018 Author Share Posted July 5, 2018 At the moment of doesn't mean in reaction to. You're quite right that anticipating contact is better than reacting to it. Would that be at the moment of flaring? Or there is no flare in this case, since flare would mean we're pulling back on stick? thanks again for the great responses so far Link to comment Share on other sites More sharing options...
Shahdoh Posted July 5, 2018 Share Posted July 5, 2018 No flare on the 2 point landing. I know its bad form to not trim out the a/c, but I find it easier to not trim the back pressure off the stick. That way, as I descend, keeping around 115-120 indicated, JUST before touchdown, release the back pressure and can grease in a 2 pointer nearly every time. Come in slower and you might as well hold off a bit longer and flare into a 3 pointer. Can come in a bit faster, but may risk ballooning/bouncing more. 115-120 is the sweet spot for me. Here is a bit more extreme approach to land, but the technique for the 2-point is the same. (End of VFAT performance) Link to comment Share on other sites More sharing options...
Weta43 Posted July 5, 2018 Share Posted July 5, 2018 (edited) Not a great landing, but if you have a 'little' bit of brake on as you touch down, the COG pitch up, and the brake induced pitch forward cancel each other out: 3YXnH43D6c0 Edited July 5, 2018 by Weta43 Cheers. Link to comment Share on other sites More sharing options...
Emmy Posted July 5, 2018 Share Posted July 5, 2018 No flare on the 2 point landing. I know its bad form to not trim out the a/c, but I find it easier to not trim the back pressure off the stick. That way, as I descend, keeping around 115-120 indicated, JUST before touchdown, release the back pressure and can grease in a 2 pointer nearly every time. Come in slower and you might as well hold off a bit longer and flare into a 3 pointer. Can come in a bit faster, but may risk ballooning/bouncing more. 115-120 is the sweet spot for me. Here is a bit more extreme approach to land, but the technique for the 2-point is the same. (End of VFAT performance) Nice looking Quick Silver skin. I'm sure Scott Yoak would be impressed! [sIGPIC][/sIGPIC] http://www.476vfightergroup.com/content.php High Quality Aviation Photography For Personal Enjoyment And Editorial Use. www.crosswindimages.com Link to comment Share on other sites More sharing options...
dcs.sniper Posted July 5, 2018 Author Share Posted July 5, 2018 No flare on the 2 point landing. I know its bad form to not trim out the a/c, but I find it easier to not trim the back pressure off the stick. That way, as I descend, keeping around 115-120 indicated, JUST before touchdown, release the back pressure and can grease in a 2 pointer nearly every time. Come in slower and you might as well hold off a bit longer and flare into a 3 pointer. Can come in a bit faster, but may risk ballooning/bouncing more. 115-120 is the sweet spot for me. Here is a bit more extreme approach to land, but the technique for the 2-point is the same. (End of VFAT performance) Amazing What is your Man/Rpm setting on final approach? Are you at idle power at touch down? Link to comment Share on other sites More sharing options...
Shahdoh Posted July 5, 2018 Share Posted July 5, 2018 RPM's are probably around 2700 because that is the cruise setting, but could be 3000. Manifold somewhere near idle to maybe like 20. I never watch it that closely, but once set, best to not manipulate either that much on approach as the torque/p-factor will twist you about a bit. I truly just watch airspeeds more than watching for those, so could be a fairly wide range of settings. For initial training, I would say work with 2700 rpm and like 15 manifold should setup a nice glide path. Link to comment Share on other sites More sharing options...
Shahdoh Posted July 5, 2018 Share Posted July 5, 2018 When I was leading the Virtual Tuskegee Airmen, I taught this technique so we could do formation 2 point landings. As lead, I used 2700 rpm and 20 manifold so that the wingman could still throttle back a bit more if needed to stay in formation. Still provided a good glide slope. Link to comment Share on other sites More sharing options...
dcs.sniper Posted July 5, 2018 Author Share Posted July 5, 2018 Thank you. Will practice with it. Link to comment Share on other sites More sharing options...
ED Team Yo-Yo Posted July 5, 2018 ED Team Share Posted July 5, 2018 For the first attempt the plane must be as light as possible. Civilian 51 and 10 percent of fuel plays a great role. Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles. Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me Link to comment Share on other sites More sharing options...
Frederf Posted July 6, 2018 Share Posted July 6, 2018 Would that be at the moment of flaring? Or there is no flare in this case, since flare would mean we're pulling back on stick? thanks again for the great responses so far Flaring usually has the connotation of touchdown mid-maneuver and it being more last moment and dynamic. I think "round out" or "level break" to be more appropriate terms qualitatively. The transition from the approach attitude to the landing attitude happens first and then given that very shallow static flight path sticking it to the runway in anticipation of contact. Ground effect will also help reduce the vertical rate naturally. But after passing the threshold at half a wingspan I am holding some back pressure since my trim is for continued descent but my pitch rate is essentially nothing. Passing threshold and the final letdown to contact is very very little pitch change to control vertical rate. I'm reducing 200 down to 50 fpm. The partial brakes on touchdown on contact is interesting and certainly should provide the desired effect. I don't know if that's kosher practice but certainly inventive. I just gave it a try with 100kg of fuel (16 gal each tank). I flew in 115 mph pattern, 105 over the fence. My approach VS was 700-1200 fpm and about 300 fpm over the fence. Within a wingspan of the ground I transitioned to a <100 fpm descent and probably 95 mph at partial power. When contact was made I didn't have to do anything at all to prevent a bounce but a tiny forward press wouldn't go amiss. To see the fuel weight effect I went back and tried it 100% (TF-51, no fuselage fuel). Trimmed for a ~200 fpm descent after passing the threshold I held some back stick until contact. Actual vertical rate was probably 50fpm on contact. At that point while I didn't have to I relaxed stick pressure and the forward trim provided a slight nose down input. I know it's not dark, wounded, and in a hurricane conditions but it was exceptionally docile without any tendency to bounce. After finding what works I went back again and tried to recreate the bounce. I found it was speed and vertical speed. Contact >100mph was putting me back in the regime where a little bit of AOA made a lot of lift. Also 100-150-200 fpm made it reappear even as slower contact speeds. My conclusion is that CG doesn't matter much, contact VS matters the most, and contact airspeed matters somewhat. I didn't find that calm flying on a sunny day to keep contact VS under 50fpm to be much of a challenge. Good trimming and a slow pace of events certainly helps. Link to comment Share on other sites More sharing options...
Shahdoh Posted July 6, 2018 Share Posted July 6, 2018 Curious Frederf, at those lower touchdown speeds, how high was the tail flying with the mains in contact with the runway? Happen to have a vid/screenshot? Link to comment Share on other sites More sharing options...
Frederf Posted July 6, 2018 Share Posted July 6, 2018 Editor default, 20% fuel, briefly 0 fpm within ground effect after round out before let down to contact. At moment of contact the sharp VS needle was pointing at the bottom edge of the white painted 0 mark on the scale. Link to comment Share on other sites More sharing options...
Shahdoh Posted July 6, 2018 Share Posted July 6, 2018 Cool, always felt the tail was dropping lower then that below 100 but never followed up. Thanks for the pic. Guess I can open up my target window a bit to like 95-120 indicated for the 2 point landing. Link to comment Share on other sites More sharing options...
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