Sling 4 Around the World

[GermanFlyer1]

Lovely work guys! Looking forward to tonight's follow! Safe, fun flying.

Twitter: @GermanFlyer1

[Athol Terence]

Hey guys,
Lots of luck from the AP team. I am soooooooo looking forward to interviewing you when you return to our shores. You have balls - BIG BALLS!
Regards,
Athol Terence.

[rainier]

OK, that gave me a few heart attacks.

For those that do not know our autopilot systems here is a brief explanation on how they work - to better understand what happened.

These autopilot systems are a bit different to a "normal" autopilot in that they are "full authority" systems as you would find in a UAV or in some military applications. A normal autopilot is completely unaware of the aircrafts attitude and simply "herds" the aircraft a bit this way or that depending on course, track and altitude errors. Of course, as everybody knows, that does not work so well when it gets a bit bumpy - if it does you have to disengage and take over.
A full authority system is different. It knows everything the EFIS knows - and that is quite a lot. It's also clever in the sense that it can do all sorts of clever calculations and at all times knows the correct pitch and bank angles to fly for any given situation - and then is also able to fly these with reference to the AHRS (artifical horizon gyroscopic system). A system like this can outperform a real pilot in turbulence (it does not get tired).

What happend in this case is that airspeed fell to zero (I assume no heated pitot tube is used). Airspeed is one of the major inputs to the autopilot system (as it would be to any pilot flying the aircraft). The autopilot would naturaly assume that airspeed has dropped below minimum allowed (which is a setting in the system) and will lower the nose to regain airspeed - however there are some fail safe systems in use and these now started kicking in using the now limited inputs to the system. Part of the system now will assume a default airspeed (we cannot use GPS ground speed in these cases as it could be very different to actual airspeed) and prevent the aircraft from doing anything silly. The total net effect is as was described a "rocking horse" pitch movement. Not too bad in daylight if you have a reference to the horizon - but in zero visibility, at night, this can have an initial disorientating effect until you realize what is going on.

My recomendation would be to set the stall speed of your aircraft on the EFIS a little higher (ASI setup) and make sure the audio low airspeed alarm is enabled (Alarm setup and routing). Then lower the minimum airspeed value for the autopilot to below this value by a couple of MPH (Autopilot - pitch setup).
Icing tends to reduce the airspeed somewhat gradually in most cases - With the above settings you will get a warning before the "rocking horse" sets in (the fail safe mechanism would have taken over correct pitch control despite airspeed reading being too low at this point). This gives you time to react and control the situation.

Good luck for the rest of the journey. PLEASE keep it safe - we need you guys around.

Rainier

[AirplaneFtyWeb]

Short Message from James: We plan to leave Reunion at 2pm SA time (12;00 Z) It is about a 19 hour leg. we are busy doing final planning and checking weather.

[Mags]

Hi Guys

Very grand so far.Rainier thank you so much for the insight into the system workings.We use them but dont allways understand the inner workings.You should come give us a workshop one day at TAF.Jean im deffinitely impressed with the wright up.Seems their some talents we not yet aware off.Good weather and tailwinds for the next stretch.




Michiel

[AirplaneFtyWeb]

Message from Mike Blyth: Delay of about an hour till about 1300Z. Light rain now and dealing with weather updates and trying to get the tracker working and customs and stuff all at once.

[Dobbs]

Delayed until tomorrow - sounds like paper work requirements , at least I will get a full night's sleep tonight

Wth Oskosh no longer a deadline to make, you guys can take now these unexpected delays in your stride. Well done so far

[AirplaneFtyWeb]

James called Mike in South Africa. The flight departure has been delayed. See what he had to say on our Latest News Page at http://www.airplanefactory.co.za/sling4atw_news.asp. Don't forget to send birthday wishes to Jean as it is his birthday tomorrow.

[grahame]

From the Sling website it appears that Reunion wouldn't allow a vfr night departure. This whole flight is being conducted as a vfr one? Wow

[Captain Durango]

Thank you for a well written account of the first leg.
You may not know this, but you are living out the adventure for all of us, so keep posting written and photographic accounts.

Bravo!

[blender]

Thanks for an engaging read Jean, you're quite the wordsmith, great flying and please keep the commentary flowing.

[jimdavis]

HAPPY BIRTHDAY JEAN

Jim

[jpitman]

Monday 9 August 2011 – Things never work out quite as expected!

OK, so you got the basic story from Mike - we’re back in an hotel room (this time much more humble!), ZU-TAF is back in the hangar, we’ve had a first class Chinese Creole meal and now we’re settling in for a quiet sleep.

Today has been a good example of how travel experiences aren’t necessarily about making physical progress, but also about the details on the way. We may not have made great physical strides since sun-up, but we’ve made lots of friends and learnt a lot about Reunion’s people, their pride and their generosity.

Laurent, who picked us up at the airport yesterday, arranged last night’s free hotel accommodation and transported us to it (some 45 minutes by car), was back to pick us up from the hotel again this morning. We stopped for a snack en route, where I managed to leave my credit card in the Patisserie. At the airport there was a crowd to meet us. Radio, television and newspaper. Reunion was expecting our arrival no less than 10 days ago and since then there’ve been four published articles. While we prepped the plane we answered a bunch of questions for media and felt very proud of our machine.

Later we were informed that the Mauritians wouldn’t allow us through their airspace without a formal application for permission – we’d been led to understand that, like Reunion, this was not required for private flights. The Aero Club instructor, Cedric, leapt into action and off went a series of emails and faxes. It would appear that these may now have reached the Mauritian Minister’s desk and we’re led to understand that tomorrow the permission will be forthcoming. Still, since we fly at night we’ll have to file an IFR flight plan – nothing new, we had to change our Reunion flight plan to IF once we entered Moz airspace at night too. The help from the members of the Aero Club Roland Garros, including the Chairman, Mr Boval, was astounding. Special thanks also to Graziella Point, a pilot and medical doctor who assisted with translation, flight planning advice and later transport, dinner and good conversation.

When I realized I’d lost my credit card Laurent was instantly onto the line to Radio Freedom. Within seconds the woman behind us in the line at our lunch Patisserie had called in to tell the radio station that she’d seen me leave my credit card. She read the Patisserie telephone number off her lunch package on radio and a flight instructor called the Patisserie which confirmed, on radio, that the card was with them. Following an explanation of our adventure to the audience and an opportunity for me to thank the Island in my best French, Laurent drove all the way back to the Patisserie to fetch the card while Graziella drove me and Jean off to a restaurant for dinner.

One great feature of Reunion is that there is a wonderful mixture of peoples and cultures. Laurent describes his first language as Creole, yet he looks to me like a Parisian Frenchman (his ancestors were among the first settlers on the island nearly 200 years ago). Graziella is ¼ Chinese, but she grew up in France. She feels entirely French. There appears to be no financial distinction between different race groups in Reunion.

Perhaps the delay isn’t too bad a thing. There were embedded storms en route and some hitches with a component of the satellite tracking system which are right now being resolved. We would have been quite “out there” without any comms at all, at night in the middle of the ITCZ storms and it feels quite good to be in a warm, quiet environment. Actually, it feels like we’ll be quite “out there” anyway, whenever it comes.

Jean and I are getting along like a house on fire and, though not without its stresses, life on the road is good. Two days in ZU-TAF already feels like an old friend. Full of fuel she’s so heavy we can hardly pull her across flat tar. But we know she’ll lift off like a butterfly and climb to 10 000 feet when called upon to do so. She’s by far the bravest of the three of us on this trip!

Please hold thumbs for clear skies and no storms tomorrow night.

James

PS – Rainier, thanks for the information on how the autopilot worked during our icing ordeal. It’s quite fascinating how technology gives a “feel”. I could sense that it was taking cues from different inputs and making good decisions about how to respond based on them – just like a human brain. Actually I think we probably could have continued under the autopilot’s control, perhaps even indefinitely without any airspeed input (the rocking/pitching probably would have put my son to sleep quite effectively!), but the ice was building up very quickly, so it seemed to make good sense to get down as quickly as possible. Thinking about it, our MGL Odysseys are probably the next bravest pilots on the trip!

Thanking Laurent for his help in Reunion.jpg

Back in the hangar til tomorrow - What can you do..jpg

Page 9 - Le Journal, Reunion.jpg

[Rob K]

Wonderful stuff James - good to see that huge smile on foreign soil again.

Godspeed for the next leg.

Rob

[Jean Crous]

God speed and the best tailwind to you guys Happy birthday Jean, what a way to celebrate your birthday

Jean Crous