RE: landing bounce
To fully answer the question, we have to establish that there are two aspects of physics involved, mechanical and aerodynamic. The landing gear and wheels act like a spring. An aircraft with zero airspeed, dropped in a level attitude from any height, will bounce to some extent (may be tough to see, but it's there). The other force in play is aerodynamic. This is the result of a relationship between the center of gravity in relationship to the chord line and what happens to the angle of attack when the wheels touch down. As the wing approaches the runway, it has some angle of attack through the air. Generally speaking, when you increase the angle of attack, the lift increases, and the airplane goes up. The converse is also true. As the airplane touches down, if the center of gravity is ahead of the main gear, the nose rotates downward, the angle of attack decreases, and the airplane loses lift and thus tends to stay on the ground. Now, remember, I said generally. If you hit too hard, regardless of the aerodynamics, the airplane will bounce because of the spring like nature of the landing gear. Now, consider the case of a taildragger. Because the CG is behind the main gear, the inertial force tend to drop the tail, INCREASING the angle of attack, and therefore increasing lift, and the airplane appears to bounce. This is why speed control on touchdown is so much more important on taildraggers than tricycle.
Posted on: 9/15/2012 5:36 AM by Author "franklin_m" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11229138

RE: Duraplane Movie
I've had a Duraplane as well, for over six years. It's been crashed many times, mostly due to me pushing it harder and harder. The fact that it's a bit heavy meant that I felt good flying it on less than perfect days, and it never let me down. Mine was powered by a used OS 40FP, which I put at least ten more gallons through it. In fact, after it's last mishap, I took all the stuff off it with then intent of finally scrapping it. Last season, I decided I missed flying it, and put it back together.
Posted on: 9/13/2012 11:59 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=11227431

RE: lights on an aircraft carrier
What's really shocking is that Penn State is paying the legal bills for the Athletic Director (Curley) and the head of Public Safety (Schultz)....gotta ask why? There's a great article in today's Centre Daily Times (available online) discussing the culture of silence here in Happy Valley. I think they're not prepared for the investigative media scrutiny they're about to face. They've manged to make Michael Vick look good by comparison. Sad.
Posted on: 11/11/2011 7:14 PM by Author "franklin_m" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10807928

RE: lights on an aircraft carrier
Well, I'm one of the ones who think that rather than riot to support a coach, we should be focused on the victims and running down everyone who knew or should have known about this and did nothing. Sadly, I think it's going to get worse before it gets better.
Posted on: 11/11/2011 1:10 PM by Author "franklin_m" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10807479

RE: lights on an aircraft carrier
Actually you're not seeing the refueling probe, it's the frame of the HUD. Airplane is a Super Hornet.
Posted on: 11/11/2011 1:09 PM by Author "franklin_m" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10807475

RE: How far do you travel?
About 14 miles over country roads.
Posted on: 11/11/2011 1:02 PM by Author "franklin_m" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10807462

RE: lights on an aircraft carrier
Here's a couple photos. Sorry the pictures aren't better, I lifted them from a videos from my Navy time. The "Dusk" one (camera on the glareshield) shows the lights in relation to the landing area. The "night" one, shows what it looks like from about 1/2 to 1/4 mile. It's dark - yep - there isn't much to look at. The lights are mostly off white. The lights down the fantail (vertical line dropping straight down in night picture) are red. There's plenty of shots of Fresnel lens close up. On the diagram, it's about 2/3 of the way down the landing area off the left edge.
Posted on: 11/10/2011 12:33 PM by Author "franklin_m" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10805906

RE: lights on an aircraft carrier
The landing area, from the round-down to the end of the angle deck is lit with off white perimeter lights. Additionally, there is center line lighting, also white. There is a sting of lights from the round-down down the stern of the ship to that align with the centerline. Lastly, the fresnel lens to the left of the landing area has a row of green datum lights with an orange-ish light in the center. See wikipedia page for diagrams.
Posted on: 11/10/2011 9:43 AM by Author "franklin_m" in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=10805713

RE: Super Tigre 40 problems
Bill, Thanks! I was reading this post out of curiosity and saw your solution to the needle valve O-ring problem. You saved me the cost of a new needle valve. I found out from Tower that the only way to get the 2 cent oring is to buy the 6 dollar needle. Ugh. Frank
Posted on: 7/31/2011 6:04 AM by Author "franklin_m" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=10647560

RE: The AMA EC needs to move on this.
Ok, so I'm dying to know what the core issue was in this event.
Posted on: 7/5/2011 1:13 PM by Author "franklin_m" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10607225

RE: RCU hanging ?
I'm running Firefox on a Linux box, and it's the same here too. I think it's because of all the flash ad content they're trying shove down our throats. In a non-scientific study, I seem to find that the sites with heavy ad content hang more often. Don't know if there's a handshake that gets lost somewhere, but that's my 2 cents.
Posted on: 6/22/2011 5:42 AM by Author "franklin_m" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10586455

RE: what new planes have that
[quote]ORIGINAL: oldtyme Thank goodness no Extra's, Cap's, Edge's or Sukoi's......................they are all so alike and soooooooooooooo boring!!!!! [/quote] Couldn't agree more. What the world doesn't need is yet more overpowered mid-wing aerobats!
Posted on: 6/4/2011 4:43 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10556135

RE: RC Pilot blamed for Collision w/ Aircraft
[quote]ORIGINAL: ira d So if a jet and glider find they are in the same airspace but the jet does not see the glider does the glider have any resonsibility to try to avoid the jet? What do you think would happen if they had a collison and it could be proven in court the the glider had seen the jet in time to take evasive action but did not because he had the right of way. [/quote] In short, YES. Each aircraft has a responsibility to avoid other aircraft, even if those other aircraft have the right of way. Per FAR Part 91.113, Right of Way rules: "(b) General. When weather conditions permit, regardless of whether an operation is conducted under instrument flight rules or visual flight rules, vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft."
Posted on: 5/28/2011 5:39 AM by Author "franklin_m" in the forum "3D Flying!"
http://www.rcuniverse.com/forum/fb.asp?m=10544679

RE: RC Pilot blamed for Collision w/ Aircraft
[quote]ORIGINAL: BarracudaHockey The whole thing was a Charlie Foxtrot from the get-go. The R/C was asked to be there and put on a demo. The R/C didn't have an adaquate spotter. The FS was showing off. The ''air boss'' didn't seem to have a handle on much. Break any link in the chain and there wouldn't have been a mishap. I said it before but it bears repeating, we have a duty to see and avoid manned aircraft. [/quote] Sounds like you've attended one of the military aviation safety schools....I went to the Navy one. They use two models, either the "Swiss Cheese" or "Links in a chain". Point is, an accident is a series of events/decisions that all have to happen in a specific order to cause a mishap.
Posted on: 5/28/2011 5:17 AM by Author "franklin_m" in the forum "3D Flying!"
http://www.rcuniverse.com/forum/fb.asp?m=10544663

RE: Futaba, or just 2.4, problems at Joe Nall?
[quote]ORIGINAL: Skaluf Hi guys, The jet crash that took place at Nall was caused by the radio installation under a metalized piece of plexi. The owner was advised against it, but a range check led him to believe it was safe to fly. Unfortunately it was proven to not be the case. Steve [/quote] With the above statement, one of two things must be true: either the published range check procedure is not reliable, or something else caused the crash. Absent telemetry, there's no way he can make this statement. It leads one to believe that the antennas were partially obstructed. Ok, with 2.4 that is indeed an issue, but what was the orientation? if it didn't have that piece of plexi blocking the signal, then it wasn't that now was it? 23 years experience attacking electronic RF systems tells me it's something else. The system, all systems, have limits. The manufacturers / distributors have yet to tell anyone what the design limits are....and they've got incentive to continue to keep that quiet. For all the ad dollars spent touting the robust nature of 2.4, to come out now would create havoc in their marketing / consumer relations. Don't kid yourselves, there's huge dollars involved, therefore huge incentive to try and blame something else rather than the most obvious - a crowded spectrum at the site and radios that are not so robust as advertised. Remember Occam's Razor - the most simple explanation is usually correct. From my post in another forum: There's any number of good sites out there that demonstrate how spread spectrum works, the different schemes and, most importantly, how the signal coding works. Dabigboy pointed out above that there are limits to this system. Despite what the distributer is saying, physics is physics. There's a limit to how much signal to noise these can tolerate, how many data chunks a receiver can miss, and the simple fact that there's a lot of RF energy in the 2.4GHz spectrum, from a variety of sources. Every time a piece of a spread signal is at the same frequency at the same time as something else, there is interference. More transmitters, RC or not, then more opportunity for overlap at any given frequency/point in time. Regardless of whether it's DSSS or FHSS, there's only a finite number of frequencies and a finite number of coding sequences. Even if the number of coding sequences is large, at what point does the number of transmitters start to load up enough points in time to the point where a receiver locks out? How "random" are the random code generators? How long does the receiver processing take? I've seen any number of systems overloaded just by making a receiver spend too much time trying to sort out what's real and what's not. Like I said, I've spent an entire career finding ways to hammer RF systems that were much more robust in their designs than RC receivers, and there's always a way. It doesn't always require fancy equipment either. However, one thing remains true....the more dense the RF environment, the easier it is to knock down a system. Regardless of what the marketeers say, there are limits to these systems. I just wish they'd share them so we can make informed risk decisions on when to fly and when not to fly.
Posted on: 5/17/2011 6:38 AM by Author "franklin_m" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10525016

RE: Jet crash at the Nall ?
[quote]ORIGINAL: VF84sluggo Reminds me of a department head meeting back in my naval aviator days: the operations officer said we should fly more, the maintenance officer said we should fly less, and the safety officer said we shouldn't fly at all...[:D] [/quote] Sounds like some of my DH meetings as well! I think my goal would be for more transparency on the design limits of the system(s) so that the RC community can make the same informed risk decisions we were able to make. I think that would be a huge step forward here.
Posted on: 5/15/2011 10:35 AM by Author "franklin_m" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10521289

RE: Jet crash at the Nall ?
There's any number of good sites out there that demonstrate how spread spectrum works, the different schemes and, most importantly, how the signal coding works. Dabigboy pointed out above that there are limits to this system. Despite what the distributer is saying, physics is physics. There's a limit to how much signal to noise these can tolerate, how many data chunks a receiver can miss, and the simple fact that there's a lot of RF energy in the 2.4GHz spectrum, from a variety of sources. Every time a piece of a spread signal is at the same frequency at the same time as something else, there is interference. More transmitters, RC or not, then more opportunity for overlap at any given frequency/point in time. Regardless of whether it's DSSS or FHSS, there's only a finite number of frequencies and a finite number of coding sequences. Even if the number of coding sequences is large, at what point does the number of transmitters start to load up enough points in time to the point where a receiver locks out? How "random" are the random code generators? How long does the receiver processing take? I've seen any number of systems overloaded just by making a receiver spend too much time trying to sort out what's real and what's not. Like I said, I've spent an entire career finding ways to hammer RF systems that were much more robust in their designs than RC receivers, and there's always a way. It doesn't always require fancy equipment either. However, one thing remains true....the more dense the RF environment, the easier it is to knock down a system. Regardless of what the marketeers say, there are limits to these systems. I just wish they'd share them so we can make informed risk decisions on when to fly and when not to fly.
Posted on: 5/15/2011 6:43 AM by Author "franklin_m" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10520899

RE: Jet crash at the Nall ?
;m just sorry to see that folks are losing airplanes as a result. It was predictable though. Once..., just PM me. It's for this reason that I'm still using 72Mhz. Not a panacea to be sure
Posted on: 5/14/2011 5:18 AM by Author "franklin_m" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10519016

RE: GS45 High Speed Needle O-Ring
I don't know that I buy that, I just did a quick search on the tower hobbies site for O-rings / gaskets....as they're similar. Any number of them at 1.50, 1.89, .89 in stock. Am I to believe that it's worth the cost to inventory, stock, and ship those, at as low as .89 cents, but it's not worth it to do that same thing with this one? example: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXPG60&P=7 I think the logic falls apart.
Posted on: 5/12/2011 7:26 AM by Author "franklin_m" in the forum "SuperTigre Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10515584

RE: GS45 High Speed Needle O-Ring
Ok, is it just me or does that seem really silly? Not like O-rings don't go bad from time to time. Seems absurd to have to buy an entire needle valve just to get that part. Unless it's just a way to extract money from us.
Posted on: 5/11/2011 5:25 PM by Author "franklin_m" in the forum "SuperTigre Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10514546

GS45 High Speed Needle O-Ring
Have a GS45 that I plan to use soon. Removed the high speed needle valve the other day and see that there's a small o-ring that's squished out of shape. When I go to look for a replacement, can't seem to find it listed separately. Sure seems wasteful to have to buy a whole new valve just to get the rubber o-ring. Any suggestions? Thanks, Frank
Posted on: 5/10/2011 10:08 AM by Author "franklin_m" in the forum "SuperTigre Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10512026

Bungee launch nitro prop plane?
Anyone ever seen a bungee launcher for a nitro prop plane? If so, would really appreciate photos etc. I fly at a grass field and want to build something fast, but without landing gear. Since I often just go with my young son, would prefer not to hand launch. I know that folks do it for electric planes, but with those you can start the engine after launch. Thanks, Frank
Posted on: 5/10/2011 6:23 AM by Author "franklin_m" in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10511654

RE: Build on a budget
I think the most fun 1/2A plane I've ever owned was the "Sure Shark" by Raindave. I built mine with an unthrottled Norvel 0.049 and just two channels. It was the saddest day of my RC flying life when it augered in due to a stripped elevator servo. What a great flying plane.
Posted on: 4/16/2011 7:32 AM by Author "franklin_m" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10465951

RE: OS40 FP for Phoenix Super Decathlon?
Thanks. I'll find a way to make the .47 ST work. They can swing a pretty big prop for their size, I guess I'll have to knuckle down and buy a muffler. Frank
Posted on: 4/13/2011 3:07 PM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10460948

RE: OS40 FP for Phoenix Super Decathlon?
;I=LXHY77&P=M]Click me![/link] [/quote]
Posted on: 4/13/2011 10:11 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10460475

RE: OS40 FP for Phoenix Super Decathlon?
[quote]ORIGINAL: opjose [quote]ORIGINAL: franklin_m I've got a Supertigre 46, the problem is that darn muffler that comes with it. Would have to cut the crap out of the cowling. I'd really like to avoid spending 36 bucks to buy a Macs muffler to fit the trough. The motor mount is angled, so even the pitts muffler I have on the shelf is not workable. [/quote] Remove the muffler
Posted on: 4/13/2011 9:12 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10460357

RE: OS40 FP for Phoenix Super Decathlon?
That's interesting, because the two I have a both strong runners. One was even used when I bought it. Probably have at least ten gallons of fuel through it. Sure, down on power some, had to replace a rod when I hydro locked it, but otherwise good. I'm full up on engines right now. But thanks for the offer.
Posted on: 4/13/2011 6:28 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10460066

RE: OS40 FP for Phoenix Super Decathlon?
I've got a Supertigre 46, the problem is that darn muffler that comes with it. Would have to cut the crap out of the cowling. I'd really like to avoid spending 36 bucks to buy a Macs muffler to fit the trough. The motor mount is angled, so even the pitts muffler I have on the shelf is not workable.
Posted on: 4/13/2011 3:40 AM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10459875

Taildragger twins?
For those of us that fly off grass, anyone aware of a decent taildragger twin?
Posted on: 4/12/2011 1:27 PM by Author "franklin_m" in the forum "Twin & Multi Engine RC Aircraft"
http://www.rcuniverse.com/forum/fb.asp?m=10458747

OS40 FP for Phoenix Super Decathlon?
Have weighed all the pieces and parts, including the radio stuff, and with estimated 8 ounces of fuel it looks like my Phoenix Super Decathlon will weigh in at 6lbs, 12 ounces give or take a bit. I'm not one of those types that double the size of an engine. I'm looking for something that can takeoff from grass, fly basic aerobatics, etc. I have a new OS40 FP that will fit perfectly
Posted on: 4/12/2011 1:22 PM by Author "franklin_m" in the forum "ARF or RTF"
http://www.rcuniverse.com/forum/fb.asp?m=10458735