 |
|
Photos
View |
|
All Photos |
Add Photos |
Emoticons |
Album View |
Mark Unread
|
|
|
|
|
|
|
|
|
|
|
|
Posted By:
Hal Brown
Date Posted:
Nov 25, 2010
Description:
Here's one reason why Rotax 914s are so expensive.
Date Taken:
Nov 25, 2010
Place Taken:
USAF Museum
Owner:
Don Maxwell
File Name:
Predator_5355_k.jpg - Photo HTML
Full size - <img src="/show.php?splash=SZPU50000h">
Medium - <img src="/show.php?splash=SZPU50000m">
Thumbnail - <img src="/show.php?splash=SZPU50000s">
Category:
23, Max Pix
|
|
|
|
|
Click on photo to view the original size. |
| Viewers
|
|
|
|
|
|
|
|
|
|
|
Read what others had to say:
|
|
|
|
|
|
|
 |
Don Hull - Nov 25,2010
Viewers
| Reply
|
| |
Maybe that will bring the price of them down!.... If somebody shoots enough of them down <br />the price should follow.  <br /><br />Is that a picture from above or below. I thought those horizontal stabilizers went up.
| | |
|
Lee Pfingston - Nov 25,2010
Viewers
| Reply
|
| |
Believe they are looking at replacing 914 with small turbine
| | |
|
Mark Callender - Nov 25,2010
Viewers
| Reply
|
| |
The Pred B has a turbine. The Sky Warrior has a heavy fuel piston engine (Thielert). Both <br />of these are larger aircraft than the original Pred A.
| | |
|
Roberta Hegy - Nov 25,2010
Viewers
| Reply
|
| |
That's the bottom you're looking at. The V tail points down.
| | |
|
Kenneth Leonard - Nov 25,2010
Viewers
| Reply
|
| |
The 914 in the predator is $80,000 US each and have little to do with the 914 we know. How many of us need a 150 lb generator?
| | |
|
Lee Pfingston - Nov 25,2010
Viewers
| Reply
|
| |
or a three stage turbo
| | |
|
Kenneth Leonard - Nov 25,2010
Viewers
| Reply
|
| |
The predator I got my hands on had a single stage turbo - I believe the same as what we use. The three stage turbo put on a rotax was an experiment by the gov to see how high they could take it and produce power. Apparently, in the pressure chamber, it ran at 80,000 ft plus. Compression ratio of 64:1
| | |
|
Dave Lima - Nov 25,2010
Viewers
| Reply
|
| |
64:1 is a big number, how long could it last at that I wonder???
| | |
|
Kenneth Leonard - Nov 26,2010
Viewers
| Reply
|
| |
With the reduced air pressure of high altitude, it calculates down to something like 30' of mercury. <br />I presume they bleed off the excess the rest of the time. Even though articles back in the 80s indicate the intent to fly them in real planes, I'd be surprised if that happened. With the triple turbo engine weighing over 500 lbs, it is more effective to use a small turboprop...and that is what we moved to.
| | |
|
Mark Callender - Nov 29,2010
Viewers
| Reply
|
| |
I was the lead Avionics engineer on this experimental aircraft. It was named Perseus B. <br />As I recall we reached an unofficial altitude of just over 65kft at Edward's AFB back in <br />1999 (and it was still climbing). Unfortunately, on the 'official' record flight later that year <br />the aircraft suffered voltage regulator failure that severely crippled the aircraft at 50kft <br />and the attempt was aborted. Perseus B never flew again. We designed for 80kft but i <br />don't recall testing the engine in the chamber over 70kft but it has been awhile. We did <br />run a slight boost at full power. We actually used 4 turbos (it was 3 stages but the first <br />stage had two turbos in parallel).
| | |
|
Kenneth Leonard - Nov 30,2010
Viewers
| Reply
|
| |
Mark - that is very cool. I should have said 'production' planes, not 'real' planes. I know around 2005, they switched the production predators from carbs to fuel injection and got a noticeable performance increase taking off above gross weight at above 120 degrees F. I vividly recall the pilot recounting to the general the upgraded plane 'lept off the runway!' and the general, who flew F-15s, said: 'sooo, now you get what, 150 feet per minute climb?' The laughter around the room was thunderous. Then we told the pilot to be careful he didn't GLOC in his control cab. Tough crowd.
| | |
|
Mark Callender - Dec 01,2010
Viewers
| Reply
|
| |
We also ditched the carbs for this aircraft. We designed a muti-port injection system for <br />the 912 core with electronic waste-gate control. If you ever make it up to Va i can get you <br />a first hand look at many cool experimental uav's.
| | |
|
Don Maxwell - Dec 01,2010
Viewers
| Reply
|
| |
Hey, Mark, does that invitation apply to folks who are already in Virginia?
| | |
|
Mark Callender - Dec 01,2010
Viewers
| Reply
|
| |
Sure! But I will make you look at the Searey in my garage first ...to make sure I'm screwing <br />it all together correctly :-)
| | |
|
Don Maxwell - Dec 05,2010
Viewers
| Reply
|
| |
Mark, it would be fun to see you again and admire your SeaRey. Carol and I get up your way now and then, as our sons live in the area. But first check your email. (If your email address here on SnD and STS has changed, let me know.)
| | |
|
|
|
|
|
|
|
|
|
|
|
| |
- About Searey.us -
- Contact Searey.us -
|
- Privacy Statement -
- Terms of service -
|
Copyright © 2024 Searey.us & Brevard Web Pro, Inc. -
Copyrights may also be reserved
by posters and used by license on this site. See Terms of Service for more information.
|
| |
- Please visit our NEW
Chapter Place Website at: chapterplace.com or
Free Chapter Management Website at: ourchapter.org. Good for all chapters, groups or families. |
| | | | | | | | | | |
