Veis

First of all, this is interference in someone else's product, on which people's lives depend. The manufacturer of the reserve will not assume safety guarantees for such a product, just as we cannot. The exception is for the main tandems, when it is impossible to prevent hard openings by other means. Are no good reason to interfere with reserves, as Rob wrote above. Old: https://rutube.ru/video/private/72f7094ed91266ac99db0dfde15b7d34/?p=wIJx5DaGwW-xyQRo6P8TRg&r=plwd New: https://rutube.ru/video/09356081ac863ee7eb5d667ef3251e88/?r=plwd

This is in the discussion about RDS: We use unified buckles for removable and non-removable sliders.

HD-grommets are already comparable in weight to buckles. We have long switched to buckles for all uses, removable and non-removable, including tandems. And we do not see any use for grommets, except for reserves.

PD are not looking for easy ways. It is enough to use monolithic stainless steel buckles that absorb heat well - instead of thin-walled grommets. This solves not only the heating problem, but also the lineset resource, the slider resource, and the opportunity to get more productivity from the slider for better openings. Initially, grommets were used for slider rings because they were cheap, easy to install and did not carry a heavy load. This is not the case now. Grommets that serve well on tandems are expensive (like Rutgerson), and require a powerful press to install.

Some orders turn out to be redundant...

https://youtu.be/1WYj2Q1yWTE HD opening (research test) from AN-26 at 300+ km/h. Nobody was hurt )

We make a voluminous pockets for a speed skydiving, some heavy duty tandems and other, but we do not use grommets. Due to the high tensile force.

The loop is only one problem. There are other problems that are no less important: 1. The energy of the PC should be maximum. To do this, the PC hat must be heavy and/or the upper coils of the spring are larger. 2. The freebag path should not limit overlapping parts, including corners. 3. But at the same time, the geometric shape of the container must remain stable during operation, especially the loop axis. 4. The density near the spring should not change after packing, so that the position of the parts does not change. Ideally, the spring should not stand on reserve fabrics. etc.

Square reserves are reliable enough, but only when there are no triggers and retarders between freebag and PC. I had a Rogallo-type (like Para-dactyle) reserve, and I didn't have complete confidence in him. Firstly, because of the large internal air volume. Secondly, because of the deployment and slowing down system.

Even I have the porosity-machine and I can compare the fabric with the reference piece, it's not a problem. The methodology and additional criteria for their assessment are more interesting (the suitability of the reserve as a whole, not only the permeability at some individual points).

Interesting. Is it possible to get a report on what criteria it was determined by, as for a technical inspection of the system by a rigger?

MARD is loved by the manufacturers of rigs. Because many dropzones began to require RSL for certain categories of parachutists in order to reduce the human factor of fatality. But manufacturers of rigs do not like RSL, because many in recent years have noticed delays in freebag's extract on some sizes and in some flight poses. Semi-exposed PC too. And RSL does not allow us to attribute such a delay to the human factor. MARD is an "RSL without risking the reputation of the manufacturer"... The number of possible reserve deployments where the delay can manifest itself is getting less by MARD etc ))

The speed is too low for AAD, but sufficient for normal PC operation. For comparison, my cutaway in research tests with similar conditions (a small ellipse, a carousel, entering a reserve at the time of unlocking 3 rings).Without any MARDs, RSL etc. https://youtu.be/wQEj7FxSIcU

Waiting for the report..

Yes, but this trigger steals some piece of energy of the PC, if deployment were without cutaway. We recently had a fatal case with suspected involvement of MARD.. The simpler the better, IMHO.

All theories based on pushing air down give an underestimate and lost relevance even before the beginning of the twentieth century. For low-speed wings, the lower surface is now mainly a means of stabilizing and providing feedback. Explanations that do not involve the mass of air and the movement of this mass, with an increase and decrease in density in significant volumes, and the interaction of these volumes with each other are also unworkable. Kutta-Zhukovsky works, especially when integrating by volume - but it is descriptive in nature, does not affect the causal relationship of the occurrence of lifting force. Kutta-Zhukovsky is a statistic of the frame of reference associated with the wing and therefore indifferent to the position in space. But at the same time, it does not deny in any way that the lifting force changes from this position. It doesn't work that way. Give specific quotes. In addition, I would like to draw your attention to the fact that parachutes are balancing craft, and attempts to change the angle of attack with the help of controls lead to a change in the alignment of the suspended mass.

The question is what is the reason - the wind or the swaying trees? The first thing that changes when the nose of the aircraft is lift is the angle of thrust of the engines. The lifting force decreases with decreasing speed, so you have to increase it by releasing mechanization. During takeoff and landing, when parachutists jump off, when engines lose thrust, etc. I trust your experience as a practitioner, and you don't have to doubt the theory if it allows you to make the right decisions. Even if she's wrong about something...

Yes, on many aircraft, with a sufficient increase vertical angle and/ or decrease in speed, the front slats fall out automatically. It is in order to increase the lifting force. Deflecting the steering wheel towards itself can both increase and decrease lift force, depending on the current mode - it increases drag to a greater extent, and changes the thrust vector of the engine. Drag is a tool for creating lift, and there is no engine thrust in parachutes, there are no slats, there are no flaps that increase the wing area, the planning mode is slightly regulated by risers and toggle lines (analogous to ailerons), at the end of landing. Therefore, the aerodynamics of the aircraft is low applicable to parachutes.

You have read familiar words, and you are arguing with the theses that you put forward yourself. What does the dependence of lift on the angle of attack have to do with it? I was talking about a profile that provides maximum lift for a given wing area, and speeds acceptable for a landing human body.

You're both wrong. I do not know the source of your fantasy, where did you read that an increase in the angle of attack leads to an increase in lift? In such a situation, the lift is increased by the release of the front and/or rear wing mechanization. Slat - makes the flow around the upper surface of the wing more dynamic, and creates a larger bubble of low pressure air. And the flap increases the surface, which perceives this low pressure from above and increased pressure from below.

It seems that you are ready to buy something from us? )

It doesn't work that way) The drag of a the front part of the wing is a way to make the air move in a certain direction, and create lift. Even the fastest parachutes have a relatively thick profile and a non streamlined front.

The weight is always compensated if the speed of flight is constant. The only difference is how big its values are. By getting maximum lift from the profile, can reduce both the dimensions and the laying volume without losing the landing characteristics. Eventually, the source of lift force is the displacement of volumes of air having mass.

I don't know if that was intended, but you essentially confirmed what I wrote about. I will add that in parachutes it is usually required to get the maximum possible lift force. And the scope of application of parachutes in which the lifting force is structurally reduced for the sake of maneuverability or speed is very limited, like CRW rotations, or swoop (and XRW).

It is usually stated in a very simplified form, only for the layer at the surface of the wing, as it could be calculated at the beginning of the 20th century. Hence the discrepancies. If you integrate for the entire volume of air affected by the wing (as is done with modern computers), then there will be no discrepancy. And the "lifting force" considered relative to the perpendicular to the direction of movement, as expected, will decrease sharply in all directions except for optimal horizontal flight.