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Archive for December, 2017
Posted by phil alvirez | Dec 28, 2017 @ 11:10 AM | 6,103 Views
browsing i found this: https://www.banggood.com/Unique-Mode...r_warehouse=CN
the proportions look great: longish wing, characteristic of high performance gliders looks promising, and long fuselage makes it look elegant. besides, the style is great too. long fuselage is not the trend in gliders, but long tail moment speaks stability, and long nose provides room for the things we need to put inside-and to balance too.
i finished it and am waiting for weather to let me fly it, although where i live means 4 months, so in the meantime i will talk about whatever regarding it.
>>>please check updates at the end<<<
there are 2 threads:
https://www.rcgroups.com/forums/show...pan-EPO-Glider
and this: https://www.rcgroups.com/forums/member.php?u=557269
index: https://www.rcgroups.com/forums/show...m-Wingspan-EPO
so you can learn about the experience of some.
if you browse at the links you will see that just as there are comments about how good the plane is, there are also problems, like poor quality parts, some size does not match (screws to hold the wing), no availability of spare parts, lack of instructions (the so-called 'manual' is a joke), too much drag at the aileron pushrods, and so on... new products are subject to iniciation, and it is not until feedback may help suppliers to correct them, but even with these problems, the plane has a lot on its favor, so will explore the posibilities...
dec 30/2017:...Continue Reading
Posted by phil alvirez | Dec 23, 2017 @ 07:42 PM | 5,679 Views
"i now belong to the higher cult of mortals,
for i have seen the albatross..."
when i was channel surfing, found a documentary on birds. it was a film with an albatross flying. i couldnt change channel or take my eyes away!
i have seen other videos and even got into discussion on how these birds fly. https://www.rcgroups.com/forums/show...ynamic-soaring. some called it dynamic soaring, and provided all kind of explanations that made sense.
but, no matter what, i still am fascinated on how it flies. still cant understand how it flies without flapping its wings.
watching those videos of albatross in flight i loose my mind. does look as if does nothing and stays so close to the waves for a long time and doesnt fall.
there are videos on it in flight. https://www.google.ca/search?hl=en&s....0.Sg76Jpg7Lc0
and to think that they fly all day long, day after day...with just a short stop to feed and then sleep at night. can you visualize that? for their entire life!
beyond the wildest dream!
Posted by phil alvirez | Dec 07, 2017 @ 01:05 PM | 5,803 Views
i read a report of a mystery problem found in a great airplane, that shows that even with planes that seemingly perform good, there are things that happen that go unexplained. pay special attention to the end of the article.
https://airfactsjournal.com/2012/11/...uring-mystery/
and things like this also happen with our models
Posted by phil alvirez | Dec 06, 2017 @ 11:45 AM | 6,242 Views
sometimes you loose radio signal, or becomes erratic. even results in a crash. checking the radio afterwards, all seems fine. and when this happens and some1 is around, or you talk to some1, frequently they say or think that is was pilot error. yes, sometimes a crash is due to that. but when the loss happens to you, with no1 around, and you did not make a mistake, you know it was not you.
then, what happens? perhaps something in the atmosphere? give a look at this report: http://cdn.intechopen.com/pdfs/16080...o_humidity.pdf and this: https://www.reddit.com/r/askscience/...r_atmospheric/
https://annals-csis.org/Volume_5/pliks/241.pdf
at the end says: In summary, our study has the following main contributions:
We show that changes in weather conditions affect radio
signal strength. Temperature seems to be the best explanatory
variable for signal strength variation and has a
negative, linear effect on signal strength in general, while
high relative humidity may have some effect, particularly
when temperature is below 0◦C.
We show that correlation between signal strength and the
studied weather variables vary depending on radio channel
and link. Applying frequency diversity will alleviate
these effects.
We show that smaller transmit power results in smaller
unexplained variation in received signal strength (in most
cases) and thus stronger correlation with the studied
weather variables
i used to fly...Continue Reading
Posted by phil alvirez | Dec 02, 2017 @ 08:17 AM | 6,370 Views
i always have been fascinated with soaring. staying up without motor. like the birds!
at the beginning, and for many years, i flew free flight, as there was nothing else available. and learned about thermals. with hand launched gliders, then towline gliders, rubber powered planes. engine powered planes.
many years later, when radio became affordable, i got into thermal at will. that is, when i learned to find them.
now with vario is easier, as it tells me the height or if the plane is climbing or sinking. but always a pleasure to me.
recently began to experience some situations where i could make my plane stay longer without a thermal, and explored the slope and dynamic soaring. i found data at a forum, that was enlightening: https://www.rcgroups.com/forums/show...ynamic-soaring
still, what i found by chance does not match what these guys say. what happened was that once i found my plane flying a little bit faster than the wind and decided to do lazy 8s facing it so it didnt go beyond the area where i wanted it to be, and noticed that it didnt sink for a few seconds (i have a vario that tells me the height every few seconds) and became intrigued. i have reached the conclusion that it is sort of dynamic/slope effect. except that this happens in midair-no hills/cliff.
the way i see it is this: when my plane is flying at a speed slighty higher than the wind, i do lazy 8s facing it. that is: fly across the wind, then turn facing it. when the plane raises...Continue Reading