![]() |
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 |
#8
|
|||
|
|||
![]()
On Tuesday, August 22, 2017 at 2:24:38 PM UTC+3, Martin Gregorie wrote:
On Mon, 21 Aug 2017 17:35:12 -0700, Bruce Hoult wrote: Of interest to glider pilots is that this project managed to successfully find and centre in thermals using only the data available from a GPS: the 5m model glider carried a pressure-based altimeter but got better results by using GPS altitude and ROC calculated from it because that was a less noisy signal than the pressure altimeter could provide. That seems very strange and completely against the experience of every glider pilot with both a GPS and a modern MEMS pressure sensor based computerised vario. Yes, I agree. All I know is what it says in the detailed description published as NRL/FR/5712--15-10,272. It is marked as an unclassified document. This work was done in 2006/7: I know nothing about the quality of electronic pressure sensors at that time and I don't recall any description of how the pressure sensor was connected to the rest of the system or anything about what, if any, filtering or smoothing was applied to the pressure sensor. Nor, for that matter have I heard anything about people using GPS altitude information as vario input for our use. The sampling rate, at least, is similar to the response rate of many electronic varios so that approach may work for us too. You can find what looks like a full description he https://www.dsiac.org/resources/jour...2016-volume-3- number-2/pursuit-persistent-isr or search on the document reference: the first search result identifies the {PDF version that I have a private copy of but the site is either dead or very slow indeed. If the above reference doesn't give enough information you can contact me off-list: the copy I have is marked unclassified. When in extreme scratching situations, the pressure altitude from my 1994 Cambridge Aero Instruments "GPSNAV" (one of the first units, hired to a competitor in the 1994 pre-Worlds in Omarama) has saved my bacon a number of times by letting me know whether I'd gained three feet or lost five feet in the last circle. By 2006/7 something used in a military project should be excellent! |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Autonomous undersea gliders (no kidding!) | son_of_flubber | Soaring | 4 | December 13th 13 05:37 PM |
ARi silverstein, aka Jeffrey Bloss, teaches aviation! | Mark | Piloting | 0 | April 29th 10 02:31 PM |
ARi silverstein, aka Jeffrey Bloss, teaches aviation! | Franklin[_22_] | Piloting | 1 | April 25th 10 06:07 PM |
Suggestion: wind energy will make gliders cheaper | RichardFreytag | Soaring | 20 | April 24th 10 06:37 AM |
Make Microsoft angry! | [email protected] | Piloting | 1 | June 30th 06 12:52 AM |