Speed bar with Bruce Goldsmith
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- Опубликовано: 2 авг 2024
- Speed bar is a control device used in paragliding that allows pilots to increase their speed and glide ratio by extending a bar between their feet. Speed bar is typically activated by pushing down on the bar with your feet, and is often used to fly long distances or to maintain altitude in strong headwinds.
The use of speed bar can vary depending on the characteristics and design of the paraglider. Some paragliders may require more or less speed bar to achieve optimal performance, and it is important for pilots to be familiar with the specific needs of their wing.
When using speed bar, it is important to be aware of the potential for increased sink rate and to use it judiciously. It is also a good idea to practice using speed bar in a variety of conditions, including strong winds and thermals, to become comfortable with its effects and learn how to use it effectively.
Overall, speed bar is a useful tool for paragliding pilots, but it is important to use it responsibly and in accordance with the characteristics and design of your paraglider.
Timestamp
00:00 Intro
00:13 When and how much Speed-bar?
00:41 Less speed - bar
01:00 MacCready theory
01:09 Upwind vs Downwind
01:21 Two step acceleration
02:18 1st step vs 2nd step
02:24 Wings are different
03:16 Speed bar on glide control
03:48 Glide on rails
04:15 Conclusion
#parapente #speedbar #crosscountry
Clear and insightful, tnx, both Bruce and Karlis!
Our pleasure!
Very useful tips, thanks guys 🙏🏼
Happy to help! 🥰
I use the speedbar during thermling at the outside of the turn of my wing...in narrow lifts..it is very efficient.
Interesting, I have not tried this. I do use it to enter or penetrated into wind sometimes, but have not tried asymmetric speed bar adjustment.
@@FlyingKarlis I am practising this since many years. If ya fly for example a turn to the right you take your right feet cross to push the bar at the left side. control at the left outside of the turn you manage best with the c strap and keep the right feet on the left side for roll on roll, means nearly fullspeed. ya even can work with the speed, more or less, if ya get the feeling by practising ya will float and turn very efficient inside thermals.
Interesting, will have a try once the thermals restart in Spring.
@@safranpollen i fly similar and use the outside c riser instead of break in certain thermals when i want to keep the wing flat but not slow the outside too much
Have to point out a big misconception mentioned in the opening statement of this video. Speed bar does NOT increase glide-ratio. In fact, it does the opposite. On bar, sink rate increases, which is where the increased airspeed comes from. Your glide ratio gets steeper as well, and you won't be able to cover as much horizontal distance. One always has to decide if the increased altitude loss will be recoverable in the next thermal or at the next ridge. The concept is that the quicker you get into lifting air, the quicker you can top out and move on to the next lift, so you want to fly fast between areas of lift, even if you sink a bit. Now, that's pretty common knowledge, known as speed-to-fly. Even though you will penetrate faster, you must sacrifice altitude to achieve this (in still air). If you get lift between thermals, or if you can spend less TIME in a headwind, that's just a bonus, but your glide-ratio is not responsible for that. There's an old saying in airplanes - " You can't stretch a glide." Your most efficient L/D speed is your best glide-ratio speed. Faster or slower results in a less is less efficient glide in still air. The only thing that really affects that speed is the weight of your rig, hence ballast.
"However, when the engine quits, or in a glider where there was no on board power in the first place, the "power" is produced by using gravity to convert potential energy (altitude) into kinetic energy (airspeed) to balance the drag. That means the minimum drag airspeed is also the airspeed where you need minimum loss of altitude per unit of time to maintain airspeed, and thus it's the "minimum sink" airspeed.
L/D max is exactly what it says it is - the point on a plot of coefficient of lift (Cl) and coefficient of drag (Cd) versus airspeed where the ratio (the distance between the 2 curves) between Cl and Cd is at its maximum. That point on the graph is the "L/D max" or "best glide-ratio speed" and the L/D max occurs at a specific AoA. The airspeed where it occurs will vary based on the weight of the aircraft. That's why you'll see differences in L/D max / best glide speed between a Schweizer 1-26A and a 1-26E. The E model is heavier, and achieves that optimum L/D max AoA at a slightly higher speed to reflect the slightly higher weight. That's also why they use ballast in higher performance gliders in strong lift conditions. Ballast increases the weight of the glider and lets the glider achieve the best L/D AoA at a higher airspeed, without having to pitch down as much to achieve it. That improves penetration for the glider.
More importantly, the best L/D speed / best glide speed is almost always higher than the minimum sink speed, which occurs fairly close to the stall speed."
it looks like the biggest misconception is in your head: there is no still air in paragliding. All you said is theoretically true in a vitural world that lives in "still air". Even just tiny 10km/h upwind can kill your glide ratio. So speed bar actually increases your glide ratio when flying against the wind. Without speed bar u wouldn´t be going anywhere, hence less glide ratio than on speed bar.
@@svetre87 - Of course there is still air in paragliding, and that is the only way to measure a glider's performance. Glide ratio has NOTHING to do with your movement over the ground, only through the air. If the air mass you're in is moving, it doesn't change your glide ratio, it only changes your proximity to the ground and how quickly you will contact it if you don't find lift. Speed-bar is to help you change your relationship with the ground, so that hopefully you can find lift before you find the ground. You will ALWAYS descend faster through the air on bar, headwind, tailwind or no wind. Do you know the difference between airspeed and groundspeed? Air track vs ground track?
@mountainflyhigh Huh? They didn't even use the word 'glide-ratio' once in the entire video?? And even if they did, its not a *big* misconception. They simply would be referring to effective glide-ratio or ground glide-ratio which one can easily pick up from context as we are not talking about any lab measured performance but practical applications.
Your whole argument is just about semantics and not any actual misunderstanding of the subject at hand.
I'd actually argue that using 'glide-ratio' to refer to glide-ratio with respect to ground makes a lot of sense because for most practical purposes, it is what we care about.
Great video , I have an older 3 liner EnB wing , can i use the C Risers to actively prevent a collapse whilst on bar ?
Glad you like it. You can, it won't be as efficient, but it dose work.
Thank you for your reply , very much appreciated .👍
Please lower the bgm volume mate❤
Anyway usefull tips,
Thanks both of you,
Would love to, YT is not offering this unfortunately. Will do for the future videos.
Can you steer an A or low B glider by pulling on the C risers while on speedbar?
That depends on the model of the glider, most A gliders do very poorly on bar so you are better off flying without it and only having it for emergency use like in strong headwind or to desend faster with big ears. The C steering will also be pretty inefficient as the airfoil will just crease and be almost as slow as brake input but using the C will introduce less force on the back of the profile making collapses less likely. In summary, ask your instructor and avoid using brakes on speedbar. :)
@@TheGrundigg thanks! What about low B gliders like Advance Epsilon?
@@davidesperelli7775 Epsilon is a good progression glider, it won't have amazing performnce or speed on bar but you can definitely use it for fun or to get out of sink or just to go faster on a strong day.
This is not really accurate anymore. Even an EN-A wing flies better a bit accelerated and C steering works quite well, of course B/C connection makes a big difference, but just with C lines it is more than enough to control most of what's needed. I fly A and B wings for fun quite often still and I use speed-bar and C control all the time, for XC flying this is crucial for efficiency.
@@FlyingKarlis thanks, I shall try it out. When accelerated my low b wing feels much more unstable, I can feel everything a bit more.
Would you use the C as you would use the breaks to avoid collapses? With that I mean just keeping contact with the wing if you feel some loss of pressure pull?
Video jsem si uložil mezi oblíbené k paraglidingu. Děkuji 🥰
You're welcome!
Hey Karlis, discovered your videos recently and have been really enjoying them, espeically as I wait for delivery of my new Base 2 Lite :). A quick question - it looks like there's three videos in this series but youtube tells me '1 unavailable video is hidden'. Any tips on how I can see it? Thanks for posting great content!
Welcome abord! Glad you enjoy the content! The 3rd video hasn't been made public yet, stay tuned it will be public soon. There's more interview videos comming out with Bruce and others.
@@FlyingKarlis Thanks for the quick reply! I wondered if that was the case, have subscribed to get the notification, looking forward to it
Audio sux
Thank you for your feedback. 🥰
Here's that MacCready speed to fly wikipedia link
en.wikipedia.org/wiki/Speed_to_fly
Thank you for sharing the link.