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topic: Gerard "Gerry" Farell (7 articles)

Ride the Wave

March 26, 2006, 10:54:48 EST

Roll Cloud

The morning glory in Australia (this is a classic photo)

Farell Baril|Gerard Farell

http://tinyurl.com/nhq8q Thanks to Gerard Farell Baril.

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Helping Bo

Tue, Jun 8 2004, 8:00:03 pm EDT

A great response.

Alek Beynenson|Burke Ewing|Daniel Broxterman|Davis Straub|Elizabeth Hagewood|Farell Baril|Francesco "Franco" Rinaldi|Gerard Farell|Gregory Knepp|Harald Steen|Henry Bittner|John Rankin|John Simon|Lauren Tjaden|Marc Fink|Matthew Bower|Maurice Wilson|Nancy Smith|Sherry Elchin|Steve Kroop

Steve Kroop at Flytec USA «flytec» writes:

Oz Report readers answer the challenge and, to date, have contributed, through PayPal alone, close to $3000. On behalf of our little buddy Bo I would like to say thank you to:

Davis Straub, Philip Morgan, Richard Pew, Jack Axaopoulos, Gerard Farell Baril, William Mong, Francesco Rinaldi, NSW hang gliding state titles, Wayne DeVilbiss, Gregory Wilhelm, Carlos Alonso de Florida, Russell Ferrier, L E Camacho, Koos de Keijzer, John Rankin, jeff Dodgen, Harald Steen, Henry Bittner, John Simon, Gregory Knepp, Maurice Wilson, Matthew Bower, Nancy Smith, Alek Beynenson, Joseph A Balbona, Sherry Elchin, David W Mercaldi, Daniel Broxterman, Marc Fink, Burke Ewing, Michael Williams, Elizabeth Hagewood, Lauren Tjaden, Geoffrey Robertson.

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Tail plane Vs. V-tail

Thu, Jul 10 2003, 5:00:03 pm EDT

aerodynamics|certification|competition|Gerard "Gerry" Farell|job|Laurent Thevenot|safety|tail|tuck|tumble

john vernon <johnv@emvertec.demon.co.uk> writes:

This is my reasoning about the ATOS incident. You may think I have a point to make because I have made tail planes, in fact I have just restarted with the help of "Heli-Ben" Cope who does the main manufacturing now, or you may, like me, believe in the added safety a tail plane can give us :-

I think there are two discussions here 1) is whether the pilot was flying the glider too slowly and 2) is about whether the glider should have recovered.

As I don't fly an Atos and am quite happy thermaling at 23-25mph on the Tsunami I will only deal with 2).

The tail plane can provide us with improvements to our glider's stability by increased pitch damping and adding positive pitching moment at negative angles of attack. From these improvements we derive additional benefits of improved thermaling feel and damping out the effects of turbulence.

Floating, negative angle tail planes provide increased damping and increased positive pitching moment at negative angles of attack and do not change the pitching moment at +ve angles of attack. However they have the disadvantage of increasing bar pressure at speed, which is why I developed the "competition stop" which allows pilots who want to exceed 50-55mph, with a tail plane fitted, to do so. The above is true as long as the glider the tail plane is fitted to is not changed from its certified settings because the tail plane is fitted

Positive angle set tail planes (as I believe are fitted to the ATOS) increase pitch damping and depending on how they are designed and set can provide some increase in pitching moment at negative angles of attack and also can have a negative effect on pitching moment at positive angles of attack. Consequently they do not increase bar pressure at speed.

I assume that, in the case of the ATOS, the tail plane has now become an integral part of the glider's aerodynamics and the aerodynamics have been tuned to meet the certification requirements with it fitted. Consequently it seems to me that there will probably be no additional or only marginal additional positive pitching moment benefit derived from it as compared to the pitching moment safety margins required for the test i.e. the tail plane basically provides added pitch damping but provides no or only marginal extra +ve pitching moment.

When I wrote the article about tail planes in Skywings a couple of years ago (you can read it at www.slipstreamcomposites.com) it became obvious that the combination of increased pitch damping and added positive pitching moment over and above certification standards are necessary to improve our aircraft's tuck and tumble resistance.

Gerard Thevenot wrote in an email recently when questioned about tail planes

"Certifications say that above a line a glider is safe, under the line it is not. It is not a true fact, the more stable the safer the glider will be. A tail plane will improve the safety of a certified glider by a big margin."

In the incident in Spain it strikes me that the aircraft had enough airspeed to recover, it had passed through the first phase of rapid rotation and speed increase where the added damping had done its job, and not apparently gone past vertical, the pilot was still holding the bar and I think had moved his weight forward, at this point the glider should have pulled out and recovered, why didn't it?.

Added pitch up would certainly have been beneficial throughout the recovery and particularly at this point. I personally believe this was an incident where, with a tail plane fitted, the glider should have recovered.

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Aerotowing PGer’s

Fri, May 16 2003, 12:00:05 pm EDT

aerotow|bicycle|cost|David Prentice|DHV|Dragonfly|Gerard "Gerry" Farell|Gordon Rigg|Hans Bausenwein|Laurent Thevenot|parachute|payout winch|PG|powered|release|tail|tow|trike|tug|winch

Hans Bausenwein <Hans@aerosport.de> writes:

Great attempt by Dave Prentice! I think the solution would be to fix a small payout winch to a Dragonfly, run the rope through a steel tube to the end of the tail and off you go. I have such a unit made by Christoph Schuhwerk an engineer and hang glider pilot from Germany.

This little payout winch only weighs 20kg, has a Kevlar drum and an exact means of setting the thrust to anywhere up to 100 kg (ideally you set it to the pilots body weight). The unit has a small bicycle bell on it that rings with every revolution. So you hear how fast you are paying out rope and can speed up or slow down accordingly.

It is usually used on a car and is ready to mount on a 50mm ball head of a tow bar. It even has a guillotine to cut the rope in an emergency. The release rope of the guillotine is run to the driver’s seat. We use a large mirror (like a traffic mirror) mounted on the bonnet of the car with big suction cups to see the pilot all the time.

The drum has 600m of 3mm spectra rope and can hold more than 1000m. I will be coming to southern Texas end of June and could bring it if anybody wants to try to fix it to a Dragonfly. Contact me if you are intersted <hans@aerosport.de>. The unit even has a DHV Gütesiegel. It is several years old, but I only have used it a little bit (less than 50 tows). Cost was around 3000 US $. I do not know how much it will cost today.

Gin Gliders have bought two of these Schuhwerk payout winches just recently to use them on an expedition to Mongolia. The expedition is not happening now and Gin wants to sell them again. Contact <gin@gingliders.com> if you are interested. Gin Seok Song also had the intention to come to South-Texas for long distance flying, but wasn't sure if he will find the time.

Mike Dillon <mikedillon@flightconn.com> writes:

It was good to hear that someone has finally aerotowed an paraglider. I've been daydreaming about this for years. The way Dave and Bobby accomplished this sounds fun, but I don't know if it would catch on, it sounds way too complicated.

I think a more practical way to aerotow would be behind a powered parachute (not a paraglider, but one of those large, low performing square chutes powered by a trike). I think they have a top speed of about 28 mph and a bottom speed of about 24 mph (maybe even slower). I've thought for a long time that this would be the ideal tug for a paraglider. I don't have the balls to try it, but it sounds like David Prentice just might - anyone?

Gordon Rigg writes:

Gerard Thevenot did some experiments aerotowing paragliders in 1996 or before using a trike. Given up as too unsafe.

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Deployment bags

Thu, May 15 2003, 3:00:07 pm EDT

Alessandro "Alex" Ploner|Alex Ploner|Angelo Crapanzano|bridle|Europe|Gerard "Gerry" Farell|harness|insurance|Laurent Thevenot|parachute|Rich Pfeiffer|safety|spin

Angelo Crapanzano <angelo@metamorfosi.com> writes:

Recently, while speaking about rescue parachutes, Alex Ploner told me in US there is quite a bad reputation for "diaper" deployment bags (flat pods with, normally, four flaps), while there is a good one for "envelope" ones (a bag normally opened on one side only). I already knew in US there was a preference for envelopes (while in Europe there is for diapers) but I didn't know it was so strong.

The deployment reliability of a rescue parachute depends mainly on the pod design; that's why I feel important to point out the differences between different concepts and, even more important, what makes a good or bad pod. I'm a manufacturer and of course my own design is my preferred one (otherwise I would make it different), but I'll try to be as general and objective as possible.

In a good deployment bag we need to have: easy extraction from the harness very low risk of accidental deployments, lines stowed inside the pod before deployment, ease of throw, very low risk of untimely opening, easy opening of the pod, staged deployment sequence.

1) An easy extraction may concern more the harness parachute container design than the pod itself. We need to have a big enough handle (remember it's always easier and safer to catch the handle using the thumb) and reachable with both hands (one could be injured or one hand could be better than the other in case of a spin).

The use of Velcro to keep the container closed is not reliable: often holds too little or too much. The Velcro should also avoided to keep the handle in place because if the pilot, at first try, peels out the Velcro but misses to catch the handle, then the handle could become unreachable (this is especially true in paragliding for dorsal mounted parachutes).

Be extremely careful there is not male Velcro on the handle itself: it may stuck on the lines loop holding the pod closed, thus impeding the opening. It's not only a theory: I've seen this happening during parachute clinics and, unfortunately, a German pilot died in Castelluccio di Norcia a few years ago, because of it.

There is one way only to know if your parachute is easy enough to extract: hang into your harness and try! Don't be too much surprised if you cannot get it out: during parachute clinics I've seen several pilots not at all able to extract their parachute.

2) Low risk of accidental deployments means the parachute must not come out by itself. The biggest improvement on this subject were the safety pins (introduced in the hang gliding world long time ago by Rich Pfeiffer) used at first as a safety for the Velcro but, if properly designed, are perfectly safe by itself. In some cases one could add an elastic or a sewing tread to hold them in position (check you are strong enough to break it pulling the handle!).

Be sure there is no way for the handle to get tangled in the side cables or in the base mounted instruments (there have been several accidental openings this way). Be also sure the pins are not too long (longer than the slack in the handle) otherwise there is no way to pull the parachute out of the container. Pins should be properly curved or flexible (straight pins could stuck if pulled in the wrong direction, as shown in several accidents) and be careful the head of the pin cannot pass through the loop (there have been several accidents this way too).

3) The lines stowed inside the pod before deployment are mandatory to reduce the chances of lines getting tangled into the wreckage (one line tangled is enough to get the parachute useless). Unfortunately there are several old pod designs where the lines are exposed.

4) The ease of throw depends on parachute weight but also in handle shape and length. A long handle makes it difficult to control the throw and could tangle on cables (some handles designed as an anchor don't certainly help). A handle attached to the pod in two points gives a more solid hold compared to the, unfortunately now common, single point attachment.

Never attach the pod to the canopy: to save some dollars in case of deployment, you definitively increase the risk of a tangled parachute!

5) Low risk of untimely opening means the deployment bag shall not open before you throw it and let it go. This can easily happen in an old style envelope pod where the handle is in the opposite side of the opening because only the elastics are holding the canopy inside the bag: if they are too old or weak the canopy will fall out before one throws it while, if they are too strong, the pod would be hard to open.

A good envelope pod design is to have both the handle and the opening on the same side, so the elastics don't have to hold the weight of the canopy. On some diaper pod designs the canopy or the lines can fall out if one shakes the pod (still holding the handle). In any case it's important to leave the right amount of slack in the bridle: the pod must not open until you let it go!

6) Easy opening of the pod is mandatory because, in case we cannot throw it forcefully (much easier to say than to do in reality), there is only the difference in sink-rate between broken hang glider and closed pod to open it. Please note that, in most common accidents, the closed pod falls faster than a broken hang glider or paraglider.

In case both glider and pod are falling at the same speed there is still the aerodynamic drag on the bridle which could open the pod. It's clear we are never speaking of big forces, so we need to have the pod open with a very light pull.

7) The correct staged deployment sequence is: bridle - lines - canopy. We first want to have the bridle coming out because we want the pod (still containing lines and canopy) to go away as far as possible to reduce the risks of entanglements. Then we want to have the lines, and finally the canopy must come out only when bridle and lines are stretched. This is the best way to reduce the chances of canopy malfunctions and to reduce the opening shock on the parachute. In a well designed pod, regardless of the strength of the elastics, the lines shall not come out until the bridle is stretched and the canopy shall not come out until the lines are stretched. Speaking of lines and bridle, I would like to point out that we need:

- long bridle to reduce the chances of a tangled parachute,

- long lines to get better sink-rate and stability from the same canopy

- short sum of lines plus bridle to get a faster opening time (it looks impossible at first, but there is a clever solution to this problem).

IMPORTANT: To check out the extraction, hang into your harness, put your thumb into the handle, grab it and pull it out slowly: the pod must come out effortlessly.

To check out a pod for untimely opening, while still hanging, stretch your arm sideway to check the slack in the bridle, then shake the pod without leaving the handle: the pod must not open.

To check out if a pod opens easy enough, put the pod on the floor then pull up slowly the bridle and then the lines: the pod must open easily without lifting the parachute and the canopy must get out easily. The deployment sequence, during the previous test must be: bridle - lines - canopy and must be correctly "staged" (should be the same regardless of the relative strength of the elastics used).

These simple test doesn't take more than 10 minutes (plus repack, which is always useful to get a fast opening) but could save your life: much cheaper and much more useful than a life insurance, but your partner could think different :-) :-)

While you are there, check out how old is your parachute: if it's more than 10 years old consider replacing it. An old parachute behaves exactly as a new one, of the same model, if you are going to deploy it at low airspeed. However parachute fabric is quite sensible to aging and ultraviolet rays: an old parachute cannot withstand the same high speed as a new one.

If your deployment bag doesn't work as it should, fix the problem if possible (and check it again!) or, much better, have an expert professional check and fix it (but check what the professional is doing too. It's your life which is involved!).

I practically didn't speak about the differences between envelope and diaper pods because it's not much important. What is important is that a pod works in the correct way and you can get it both with an envelope or a diaper one. Remember:

- Pods which don't stow the lines inside increase the chance of a line getting tangled.

- Old style envelope pods with the handle on the opposite side of the opening are dangerous because, in case of warn-out elastics, the canopy can easily fall out untimely (it happened to Gerard Thevenot: the pod came out of the harness but the parachute stayed inside!)

- Pods without a correctly staged opening sequence, bridle - lines - canopy, increase the risk of entanglement and malfunctioning.

Well… of course I do prefer my 5 flaps diaper pods because they fulfill all the previous requirements (as a good envelope one) but are "softer" to better adapt to the harness container, require less force to open and, when open, let immediately the canopy fully free.

If you ask a good American manufacturer I bet he would agree on everything… except the last sentence :-)

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Tsunami/Top Secret

Tue, Apr 15 2003, 5:00:05 pm EDT

competition|fairing|Gerard "Gerry" Farell|John Vernon

John Vernon <johnv@emvertec.demon.co.uk> writes:

Without asking David or Gerard directly, but relying on my observations at Chelan last year and my own Tsunami, the differences are minor:

1) Competition A frame - can be purchased from Gerard. Drag factor for the section is by far the lowest I have seen for a low Reynolds number upright/basebar section and I have compared all available wind tunnel data (for instance its probably 50% of the WW slipstream test data at 20m/s {45mph) , this possibly represents 0.2 of a point of glide over the same glider fitted with the best of the rest at around 15-16:1 glide and 20m/s.

2) Front wires ½ way up uprights - not standard

3) Wooden profile on keel top to keep sail profile in centre section - benefit, don't know - easy to fit

4) carbon nose fairing - can be purchased from Gerard I believe

5) Carbon inserts inside sail at tip instead of Mylar - keeps profile better at speed - benefit unknown - fiddly to rig every day I think.

6) Wing twist - and setup - I think no change - mine was set up to the measurements taken from David's glider.

7) Thin section aerofoil fairings over everything extraneous - keel extension post for flaps, hang loop

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WPRS »

Tue, Jul 23 2002, 5:00:01 pm GMT

Sarah Bowyer|Alessandro "Alex" Ploner|Andreas Olsson|Antoine Boisselier|Anton Raumauf|Attila Bertok|Betinho Schmitz|Bruce Barmakian|Christian Ciech|David Chaumet|Davis Straub|Francois Isoard|Gerolf Heinrichs|Gordon Rigg|Guido Gehrmann|Johann Posch|Jon "Jonny" Durand jnr|Josef "Zwecki" Zweckmayr|Manfred Ruhmer|Mario Alonzi|Michael Huppert|Naoki Itagaki|Oleg Bondarchuk|Oliver "Olli" Barthelmes|Paris Williams|Richard Walbec|Robert Reisinger|Rohan Holtkamp|Steve Elkins|World Pilot Ranking Scheme

http://www.fai.org/hang_gliding/rankings/class1/
http://www.fai.org/hang_gliding/rankings/class5/

Sarah Bowyer at CIVL got right on the case and got the new world rankings out right after the Worlds:

Class 1:

Position Name
1 Ruhmer Manfred
2 Heinrichs Gerolf
3 Boisselier Antoine
4 Rigg Gordon
5 Bondarchuk Oleg
6 Gerard Jean-Francois
7 Alonzi Mario
8 Reisinger Robert
9 Gehrmann Guido
9 Olsson Andreas
11 Williams Paris
12 Holtkamp Rohan
13 Walbec Richard
14 Richardson Ron
15 Palmarini Jean-Francois
16 Schmitz Betinho (Carlos)
17 Durand Jon Jnr
18 Zweckmayr Josef
19 Baier Bob
20 Barthelmes Oliver
20 Bertok Attila

The 2001 Australian Meets were dropped, so the Australian pilots suffered a bit.

Class 5:

Position Name Country
1 Ciech Christian Italy
2 Ploner Alessandro Italy
3 Posch Johann Austria
4 Straub Davis USA
5 Raumauf Toni Austria
6 Chaumet David France
6 Huppert Michael Switzerland
8 Barmakian Bruce USA
9 Elkins Steve UK
10 Itagaki Naoki Japan

The Worlds, the Europeans, the Floridameets, and the Australian meets count big time for WPRS points. The top rigid pilots didn’t fly in the Europeans, and too few flew in the Australian meets, but they did fly in Floridaand at the Worlds in Chelan and Spain. It is clear that the Floridameets and the Australian meets should be as valued by CIVL as the Europeans. They are international meets.

The pre-Worlds in Brazilshould be well attended and that will affect the Class 1 ranking. Again the Brazilian pre-Worlds should be considered as valuable as the Europeans.

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