If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#17
|
|||
|
|||
The Yellow Triangle
On Thursday, 18 February 2021 at 13:11:35 UTC, Eric Greenwell wrote:
Nicholas Kennedy wrote on 2/16/2021 4:56 PM: On many German gliders on the ASI is a yellow triangle. This Yelloe Triangle on my ASw 20 and my LS3a is the factory recommended approach airspeed. This speed is 49 knots. This has bothered me for a long time now, I think the factory did alot of pilots a disservice by putting this, to me anyway, very low number on there. On both the above gliders, the max speed, normal landing flap flaps down, is 86 knots. About 15 years ago my Gold Seal flight instructor Bob Faris, CX,indicated to me in his LS3 he planned on a much higher speed in the pattern, like 70-75 knots depending on conditions. I followed suit ever since. Since so many gliders have 49 knots for the Yellow Triangle, I think this might be a regulatory requirement, not a choice by the glider manufacturer. Perhaps gliders are required to have an approach speed no higher than 49 knots at a certain weight with the regulation required control authority. -- Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me) - "A Guide to Self-Launching Sailplane Operation" https://sites.google.com/site/motorg...ad-the-guide-1 In the EASA CS22 specification for ASI markings it includes "a yellow marking (triangle) for the lowest approach speed (at maximum weight without water ballast) *recommended by the manufacturer*". (My stars). As far as I can see there is neither a set value nor a formula for deriving it from e.g. stall speeds |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Tales Of The Bloody Triangle | [email protected] | Soaring | 36 | March 12th 21 12:25 AM |
OLC FAI triangle geometry different than FAI | [email protected] | Soaring | 1 | September 5th 15 12:41 PM |
200km/hr 100km triangle | Tony[_5_] | Soaring | 2 | January 14th 15 04:05 PM |
500 km Triangle at 306 km/hr in Argentina | Paul Remde | Soaring | 36 | January 3rd 07 08:48 PM |
FAI triangle in SEE YOU | Paul Feltz | Soaring | 2 | July 7th 04 07:46 AM |