Questions for John Lear

Originally posted by buddhasystem
To illustrate that it's rather silly to ask me whether the mean density of the Moon is roughly 3.3g/cm3. Now, do you get that?

No, I don't get it.

John's figure of 3.3 was accurate to one decimal place. Why you typed sixteen decimals for pi eludes me? You should have typed 3.1 for pi, keeping with the one decimal place accuracy that John's figure offered.

Occam's Razor would suggest that by typing sixteen digits for pi, that you were showing off your memory skills, when it really wasn't necessary. It's just as well I don't subscribe to Occam's Razor. Besides, you're human, so I don't really know what motivated you to type pi to sixteen decimals.

Originally posted by tezzajw

Originally posted by buddhasystem
To illustrate that it's rather silly to ask me whether the mean density of the Moon is roughly 3.3g/cm3. Now, do you get that?

No, I don't get it.

OK, let me try again.

Occam's Razor would suggest that by typing sixteen digits for pi, that you were showing off your memory skills, when it really wasn't necessary. It's just as well I don't subscribe to Occam's Razor. Besides, you're human, so I don't really know what motivated you to type pi to sixteen decimals.

John's question was patently redunant. So was my post of 16 decimal places. I thought you would make the connection.

Originally posted by buddhasystem

To illustrate that it's rather silly to ask me whether the mean density of the Moon is roughly 3.3g/cm3. Now, do you get that?

I'm not sure. Please tell us how the mean density of the Moon of 3.34 g/cm3 is arrived at?

Is it:

1. Wikipedia?
2. Moon density assumed to match one sixth Earth's gravity?
3. Moon rocks?
4. Moon measured shock waves?
5. Fluctuations in observed longitude?
6. Keplers third law?
7. The tooth fairy?
8. Alice in Wonderland?

Tell us, BS, how the average density of the Moon was arrived at, to be 3.34 g/cm3?

Thanks.

This paper might help you find what you're looking for.

www.ucl.ac.uk...

Originally posted by johnlear
Originally posted by buddhasystem

To illustrate that it's rather silly to ask me whether the mean density of the Moon is roughly 3.3g/cm3. Now, do you get that?

I'm not sure. Please tell us how the mean density of the Moon of 3.34 g/cm3 is arrived at?

I already posted this for you in the upper portion of page 95 of this thread. Do your homework.

reply to post by johnlear


Anyway, before the race I had gotten some tips on the best rpm for the R-2800's by Lt. Col. Ted Sturmthal one of the B-70 pilots who worked the test pilot's school at Edwards.

cool beans, Capt Lear...fun info...Wondering what MP and RPM worked best in the R-2800? Let's see, at Reno, it's what? about 4500-5000msl?

Before anyone gets mad, I write this just out of prurient interest in what Capt Lear posts. He has lived an incredible life (oh, shoot, that sounds condescending, it's not meant to...). I just think it's nice to be able to make a point, in the midst of a discussion, that might be a little off-topic, to some, but can be incredibly interesting to others.

It's just, on another thread on ATS, I was criticized by a member who thought I was rude. One thing I know about ATS is: Speak your mind, but be polite. After I was called an 'imbecile' (and the member subsequently banned) I felt it was appropriate to say it was good to see him/her bannished.

Thanks, sorry for intruding. Hope it gave a little comic relief, at least.

[edit to add]...I've never flown 'round' engines, I certainly do not have that varied a background as Capt Lear...that's why it's fascinating to me.

Thanks

[um...second edit...I suppose a TurboJet is 'round'...I meant I've never flown Radial Piston engines. Just clarity.]



[edit on 19-12-2007 by weedwhacker]

[edit on 19-12-2007 by weedwhacker]

Originally posted by weedwhacker

cool beans, Capt Lear...fun info...Wondering what MP and RPM worked best in the R-2800? Let's see, at Reno, it's what? about 4500-5000msl?

The B-26 had R-2800-79's (Bendix magnetos). Take Off power was 52 inches and 2800 rpm.

I flew the Convair 440 in Cambodia which had the R-2800 CB16/17. The difference between the CB-16 and CB-17 was whether or not you used 100/130 or 115/145 fuel.

If you used 100-130 your engine was classed as a CB-16.

If you used 115-145 your engine was classed as a CB-17.

As you may remember it was U.S. Air Force General James H. Doolittle who invented 115/145 fuel he worked for Shell oil when he was not working for MJ-12).

When you used 115/145 octane fuel and water injection you could boost the MP to 62 inches. In Cambodia (Phnom Pehn) for some reason ( I never figured out why) we had plenty of 115/145 fuel. And we had water. So we could use 62 inches of MP. Using 62 inches of manifold pressure we could take off with a heavier load. (Of Cambodians flying to Battambang to buy rice at a better price than in Phnom Pehn where the Chinese had inflated the price. I have 1000 feet of super 8 film documenting this.)

However the R-2800-79 had none of this. What Col. Sturmthal told me was that if I backed off the RPM to 2700 I would get a better true airspeed. And that’s why I passed the P-51. (Stead Air Force Base was about 5046 ft. msl.)

Fun info? Not half as much fun as actually flying it. My best to Ted who passed away a few years ago.

Ted, I miss you buddy.

reply to post by johnlear


Thanks, John.

Good information.

Best to you and yours in the Season

reply to post by johnlear


Yeah...generally it makes sense to decrease RPM to get a better 'bite' from the prop blades...but only up to a point...can't overload the engine, so it's a balance between the RPM and MP, of course. Naturally you have to get the mixture right...maybe a little rich, but not too much? Work the engine, but cool it with a richer mixture...and watch the MP go up?

Doubt if you had Cyl Head temp guages on the A26?!? You had you hear it, and feel it, and know it, right?

Originally posted by weedwhacker

[Yeah...generally it makes sense to decrease RPM to get a better 'bite' from the prop blades...but only up to a point...can't overload the engine, so it's a balance between the RPM and MP, of course.

Correct.

Naturally you have to get the mixture right...maybe a little rich, but not too much? Work the engine, but cool it with a richer mixture...and watch the MP go up?

No. The AUTO RICH setting took care of it.

Doubt if you had Cyl Head temp guages on the A26?!? You had you hear it, and feel it, and know it, right?

No. All recips had CHT. CHT was not a consideration with ADI (water).

In Lo blower the max was 204 degrees C and 1100 BHP at 2300 RPM.

In Hi blower it was the same. 204 C at 1000 BHP at 2200 RPM.

Thanks for the post.

reply to post by johnlear


We had the option of using the 'water injection', actually it was, as I recall, a mix of water and alcohol, on the Swearingin 226 that I flew, long time ago...just for the purpose, as you mentioned, as a boost. At Scenic, the converted 402s, with the Allison engines, did not have the alcohol/water injection option, hence they suffered when ambient temps were high. I did hear, from guys I flew with, that the early B707s had water injection too, but I'm sure you know more about that than I do...

We used to joke about the JATO on the Swearingen...it was supposed to provide thrust after an engine failure at V1 to comply with certification standards, as the gear retracted after lift-off. We joked about the JATO just providing a smoking trail to the smoking hole...but, that was then, and it's not very funny now.

For non-pilots here, and please correct me if I'm wrong, the "water" mixture could be introduced into the fuel/air mixture of either a Recip or jet engine, usually during takeoff...depending on how much water/alcohol was in the tank, to provide additional cooling and therefore additional thrust. I know, I did not explain it well, but perhaps Capt Lear can expand on it, if he cares to.

OH! This is a question for John Lear thread....ok...umm...Capt Lear, I hope you have a happy and safe Holiday! Question is...can you come back and tell us about your adventures?

Best to all, and to all, a Good Night.

Hey John, I have a question for you. If you were assigned this route, would you take it?

Bad Location

Happy Holidays.

Originally posted by IgnoreTheFacts

Hey John, I have a question for you. If you were assigned this route, would you take it? Happy Holidays.

I never went into Tegucigalpa. But as bad or worse was going into Guatamala, at night in rain and landing downhill. Latacunga, Ecuador was always a challenge especially at night in rain.

When ATS gets the video working I will post some of the film I took landing at little strips in Laos. There was one called Site 32 (Boum Long) which was about 5000 msl and it sat in a little bowl surrounded by mountains. It was a one way dirt strip which means you land towards a cliff and takeoff the other way because you would never clear the cliff. I've got some good video of that strip.

I forgot to mention the airpot requiring the steepest bank on short final is Gitmo. You come northbound on base leg and the Cuban fence line is barely a mile from the end of the runway. You can't stray over the fence line (or you w3ill be shot at) and you have to keep it well to the left. So when you get almost parallel with the runway you make a steep, diving right turn onto the runway. Gitmo tower always thanks you for these steep diving turns because they don't have to fill out any paperwork if you do it correctly.

Some guys at Kalitta crashed there in a DC-8 in the early 90's. They tried to do that approach when they were dead tired from too much duty time. They clipped their wing tip in the steep diving turn. Crew got pretty banged up, the f/o lost a leg. The airplane was totaled.



[edit on 21-12-2007 by johnlear]

Originally posted by johnlear
There was one called Site 32 (Boum Long) which was about 5000 msl and it sat in a little bowl surrounded by mountains.

"Boum Long" is a telling name for a short strip

My respect.

Sorry to the management for getting mad.

Yes Bhudda, I even love the serial killers too, and I believe it's very unfortunate that they have to be put to death or confined in order to protect other people. I love all of humanity, all life on earth, and based on the way you replied to my post, I don't think that you feel the same way as I do.

Peace to John

reply to post by johnlear


Hey, Capt,

I've never been to Tegulcigalpa either, but I think Quito is almost as bad, if not worse. Your story about Laos was intertesting, and hair-raising.

Thanks

Oh dang, now that I know this is here I have about a thousand questions but I will stick to a couple a week.

Back to grenada, what are your thoughts on why US Medical Students were doing on a Communist Island.

Do you think Regan was responding in grenada so he did not look impotent for not responding in Beirut (remember he said that he would not let things slide after Carter and the Iranian Hostage Crisis)

Wasnt it just a red for red trade out, just what was really going on there, because we both know they might of been able to land a backfire there but it was way too small for any bears or blackjacks. What is your Opinion, you were A-listing around that time.

OK it is almost the end of the week so I will cast my lot a second time

You know I have not been in asia in sometime and was asking a certain friend about the currents with the Golden Triangle as with the new current events it seems to have fallen off the radar, but there is too much cash there for that. What do you know?

[edit on 22-12-2007 by birchtree]

Hello John,

Merry Christmas!! (It's still Christmas here, at least for 11 minutes any way)

It seems that in your debate with B.S. you have missed my question in regards to "reround time".

Originally posted by DrZERO

Originally posted by johnlear
. . . Our scientists have reround time 3 times now in an effort to fix something. Each time they reround time it made whatever the problem was worse. I have no more details than what I just told you.

Hello John,

I have been following this thread from day one, although for the past few months I have been "off the grid." It is great to get back and catch up. Thanks again for all your insights and of course your moon photo thread (which I have not been able to catch up on yet!!)

Of everything you have written the above quote fascinates me the most, I know you say that you have no more details, but can you at least impart where you uncovered this information or what lead you to this belief.

thanks always for your time and knowledge.

Just super curious about this.



[edit on 26-12-2007 by DrZERO]