Flying in turbulence

The first time I flew in turbulence was 2007-01-05. It was a solo flight from KSEE to KSZP (Gillespie in San Diego to Santa Paula) a few weeks after I received my pilot certificate. I had flown the route a few times before, but always in clear and calm weather.

This time, it was a bit windy when I took off - nothing major. I opened my flight plan and got flight following, and proceeded to climb to 6500 feet. After turning west over Ontario, I began to get a bit of bumpiness. Just before Burbank there are some hills that extend south from the San Gabriel mountains - these force air upwards. When I reached that area, I was instructed to contact So Cal Approach on a new frequency - 125.5. I dialed in the radio and called, "So Cal Approach, Cherokee eight zero seven five charlie, level six thousand five hundred." I was acknowledged and given Burbank's altimeter.

A few moments later I hit a moderate downdraft - my headset tapped the ceiling of the plane; I pulled back a bit on the yoke and climbed back to 6500 feet. Then, a significant down-gust hit and I dropped 500 feet or more in a matter of seconds. I hit the ceiling and my cell-phone flew out of my shirt pocket and bounced off the ceiling. So Cal Approach called, "Cherokee seven five charlie, state altitude," to which I replied "Seven five charlie attempting to maintain six thousand five hundred." A King-Air heading the same direction (the only other plane I saw the entire trip; usually you see five or six) confirmed that we had "moderate chop."

After that, there wasn't much more excitement. I flew my approach over Fillmore into Santa Paula high, but the wind was not gusting in that area. I landed normally and parked the plane - but I now felt like a pilot and not just a driver. Since then I've been in other occasions of moderate turbulence, such as last weekend in the Banning Pass, and they don't bother me. I do know to keep all items securely fastened, though!


Using sz to transfer files via an existing SSH connection

If you are using KDE's konsole, it has built-in support for the Zmodem protocol.

I often SSH into remote machines via "hopping" SSH which makes it annoying to copy files back. But installing lrzsz on both my machine and the remote machine, and using konsole allows me to type:

sz file.txt

And konsole will ask me where I want to save it on my local machine. I've heard it works in Tera Term, also.


Adobe Flash 10 on Ubuntu with Chrome

I was trying to use Chromium on Ubuntu 10.04 Lucid Lynx, and Flash was working, but about:plugins revealed that it was version 9 whereas I wanted 10.

It turns out that all I had to do was delete ~/.mozilla/plugins/libflashplayer.so which was left over from long ago. I'd already enabled Adobe Flash 10 in the Ubuntu Software Manager, and once that file was gone, a restart of Chrome let it see the system Flash player.


Syntax error near unexpected token `)'

I was trying to make a case statement in bash, and was getting this error:

./check: line 8: syntax error near unexpected token `)'
./check: line 8: `      1)'

Turns out this is the error you get if you forget the ;; at the end of each code block.


Ubuntu 10.04 Boot Issues

I loaded Beta 2 of Lucid Lynx on a machine; it wouldn't get past the splash screen. I had to hit the spacebar during the Live CD boot to get it to show the boot log; this prevented the splash screen from loading and allowed me to install.

But it wouldn't boot afterwards; it would lockup in the splash screen. Turns out that the menu fr Grub 2 can only be accessed if you hold SHIFT down while booting; then you can remove "quiet splash" from the kernel command line, and boot with CTRL+X.

After it loads, edit /etc/default/grub and change CRUB_CMDLINE_LINUX_DEFAULT to:


Then run update-grub (the above has to be done as root), and the system will continue to boot correctly. The bug seems to be in a package called plymouth; perhaps it will be fixed later.



I'm going to get a burger.


Windows 7 not seeing SATA drives

I was trying to install Windows 7 on a system, and it wouldn't see the SATA drive. All evidence pointed to the drivers being correct and not needed; but the drive wouldn't appear.

Finally I determined that because the drive had a dynamic disk on it, Windows 7 setup wouldn't even acknowledge that it existed. I booted Ubuntu and wiped the partition table, and then it worked fine.


Bringing a recalcitrant SiS ethernet adapter up

I have a SiS900 Ethernet controller that I could assign IP and IPv6 addresses to, but I couldn't bring it up. mii-tool reported that the link was negotiated, and it had worked before my recent kernel compile.

I tried everything I could think of, and recompiled the kernel over and over again. Finally I realized that the other thing I'd changed was turning off SMP support - I turned it back on, and it worked! I think that the card was in INT 19 or something, and I needed SMP support to reach those higher interrupts, even though I had a single core CPU.

Fixing max open files (1024) is smaller than max sockets (4096) errors

If you are running BIND, you may be seeing errors like this in your logs each time you reload or restart named:

Feb  9 22:22:17 mail named[19053]: max open files (1024) is smaller than max sockets (4096)

This is caused by the default number of files that a process can run being set very low, to 1024. By default, in include/linux/fs.h:

#define INR_OPEN 1024           /* Initial setting for nfile rlimits */

You could edit that line and recompile your kernel, but that would involve doing that every time a new kernel was released. An easier option is to edit /etc/security/limits.conf, and add the line:

named        soft    nofile        4096

This sets the default limit for the named user to 4096. Then, edit your named.conf and add

files 4096;

in the options section. Note that you're have to stop and start the named daemon, and not simply run rndc reload, because it needs to actually exit for the changes to take effect. Now the warning will be gone!


Unicode entry in Ubuntu

To enter Unicode characters in Ubuntu, simply hold down CTRL+SHIFT+U which will create an underlined u: u Then type the hex code for the character you want (with no 0x or anything like that), followed by enter.

∎ (That's 220E, the "QED" character).