High performance aircraft?

[corvairkr]

I reckon youd be changing channels pretty regularly at cruise, and as to doing triangulation calcs........by the time they were done you'd be searching for the next station. then again, perhaps the distance a tacan will work at, at 70,000ft might be a tad longer cause I expect that line of sight is pretty impressive

Here we go.....

 

http://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Astro-Inertial_Navigation_System

 

jason

 

 

[David Pavlich]

Hi David.There is a guy here in Oz that bought a V tailed Bonanza before he had even one flying lesson.He found a instructor and school that taught him in his Bonanza from scratch. He had always loved Bonanzas.He didnt want to fly anything else.Since he owned the aircraft, the extra time it took him to gain his PPL (as compared to training in a less complexed aircraft) didnt faze him.I read about this in a local magazine years ago.

Now this brings back memories! My Dad was a flight engineer in a B17G and when he got out at the end of the war, he got his ticket. He flew for a company in Ohio called Beckett Aviation and he flew the ole' V-tail Beechcraft! I remember as a youngster going with him to the airport and listen to him talk to the other pilots. Why the heck I never followed up and got my license, I'll never know.

 

David

 

 

[Old Koreelah]

Here we go.....http://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Astro-Inertial_Navigation_System

jason

Fascinating article, but not much about navigation. I believe Inertial Navigation was originally developed for submarines, so that they would not have to risk detection by coming near the surface for a fix. In aircraft it was phenomenally accurate. I presume the microscopic accelerometers in iPhones are derived from this technology. So many consumer products benefit from military spending.

 

 

[Guest Andys@coffs]

Fascinating article, but not much about navigation. I believe Inertial Navigation was originally developed for submarines, so that they would not have to risk detection by coming near the surface for a fix. In aircraft it was phenomenally accurate. I presume the microscopic accelerometers in iPhones are derived from this technology. So many consumer products benefit from military spending.

They may well be accurate today, but the F111 INS required regular "Updates" from the radar to maintain accuracy. I noted that it was not rare to see those ferrying long distance over the oceam to have a handheld GPS so they could update the INS at regular times. INS's (at least of that vintage) drift, small amounts to start with but increasingly exponential over time as the error increases.

 

I have an electronic AH in my J230 that is based on the Company I work for Laser ring gyros, which mount on a circuit board like all other semniconducter devices. They still drift, but are made accurate with a flux gate semiconducter that senses magnetic north. The same AH also has a DG function due to that flux gate. The irony is that I purchased this at a not insubstantial price, in the context of a single individual, the INS in the pig, probably was worth 4-5 extra zero's in the price and isnt as accurate. my guts of this device (ignoring the display) fits in a box thats 6cm x 10cm x 15cm and if it tipped the scale at 300gms Id be suprised. The Pig inertial fits in a box roughly 2ft x 2ft x 2ft, weighs from memory around the same as a bag of concrete and if you foolishly moved it while the gyro's were running down ( I did this once as a unreasonable demanding flight crew required) then you had to deal with gyroscopic precession and you wandered all over the place like a druken idiot knowing that above all else to drop this thing would mean sustained pain and agrevation (and that happened when I everso slowly pulled it out and then another pig went over the top fast and I involuntarily ducked....the look on the crew face as I staggered all over the place was amazing....so was their sheepishness when I finally got in under control and yelled at them that was why we didnt do things like that!!!)

 

Andy.

 

 

[Wayne T Mathews]

I know I shouldn't laugh, but jeez Andy, come on, from a black hander onlooker's perspective, watching a queer trader trying to control one of those old INSes with the gyros still spinning would have been as funny as... Would have stopped being funny in a hell of a hurry if you'd have dropped it though...

 

 

 

[facthunter]

The early INS were mechanical and DID drift You would usually get significant errors after 3 hours or so. You would do updates on a ground station where possible and that would "drag" it back to track. One plane I flew had 3 systems and compared one to the other and the one that strayed was rejected. Each system was worth about half a million dollars. You get better results from a Garmin 296 for bugger all today. (Though it's obsolete now.) The main advantage with INS is it's independence from satellite or ground facilities. Nev

 

 

[dazza 38]

I know I shouldn't laugh, but jeez Andy, come on, from a black hander onlooker's perspective, watching a queer trader trying to control one of those old INSes with the gyros still spinning would have been as funny as... Would have stopped being funny in a hell of a hurry if you'd have dropped it though...

Talk about nearly dropping things.I nearly dropped a pig spoiler actuator off the scaffold I was standing on at 482 SQN. That would have ended in tears.

 

 

[facthunter]

It was like that when I opened the box, boss, Honest!!!. Nev

 

 

[Guest Andys@coffs]

That actuator (if its the one Im thinking of), is the main landing gear ram actuator, weight wise Im guessing that my 20kgs for the INS might well have been light compared to this sucker, that actuator opens the main gear door forward directly into the airflow as a spoiler. In the time I went up in the pig the pilot opening that sucker in flight was like riding a pushbike flat out straight into a brick wall!!!!! and was yet another reason my head in helmet acted like one of those pens that has a pretend head on a spring. Instead of bouncing uncontrolably against the canopy to the side as it had been as he was tossing it around for the rest of the flight, when the spoiler was deployed I felt the need to headbutt the radar display.

 

I certainly had much more respect for aircrew neck muscles and well understood when they came back from complex missions why they sometimes stunk like a skunk!!

 

Andy

 

 

[dazza 38]

Hi Andy, I nearly dropped a out board wing spoiler actuator. It weighed about 20 Kgs ( I guesss) .I nearly dropped it because it was covered in H-515 Hydraulic oil.It was a bit slippery to hang on to.

 

 

[Hongie]

lol back to the topic guys.. and if the OP's question is in regards to the RAAus definition of HP or LP, S2.01 subsection 8 and 9. to paraphrase, any aircraft with a normal cruise of greater then 80 knots is deemed to be HP, and anything under 80knots is LP

 

 

[Tomo]

That would have ended in tears.

Reminds me of a wedding once, it was so moving even the cake was in tiers...

 

 

[Guest Andys@coffs]

Reminds me of a wedding once, it was so moving even the cake was in tiers...

Its amazing you learn something new every day on here...I never knew cakes were female......

 

Which is not to say I havent seen males crying at a weding, I have, but its usually at the end when the daughters gone and the bill arrives. Females will always think it was the former that caused the tears, us males know without doubt it was the latter.

 

Andy

 

 

[facthunter]

Watch out for wedding cake Tomo. They have done a lot of research on female libido. There is a chemical that suppresses it. It's been found in wedding cake. Nev

 

 

[deltacharlie]

Reminds me of a wedding once, it was so moving even the cake was in tiers...

Careful, Tomo. Guernsey does the jokes here.