Uncle Fuzzies take on Self Launchers

On Friday, September 20, 2013 4:36:34 PM UTC-4, 2G wrote:

When you have a MG you can decide when and where you are going to launch (yes, you don't have to go to an airport that has tows!).

A pilot with first rate MG landed for lunch at the airport where I normally launch. He took an aerotow to relaunch (after lunch) because he said that he felt nervous about the possibility of an engine failure when launching from our "short" 2600 foot runway. He is very familiar with the airport. (Admitedly, off runway landing sites are limited.)

Is it a common (and prudent) precaution to take an aerotow with a motorglider if you have that option?

son_of_flubber wrote, On 9/20/2013 8:42 PM:
On Friday, September 20, 2013 4:36:34 PM UTC-4, 2G wrote:

When you have a MG you can decide when and where you are going to
launch (yes, you don't have to go to an airport that has tows!).

A pilot with first rate MG landed for lunch at the airport where I
normally launch. He took an aerotow to relaunch (after lunch)
because he said that he felt nervous about the possibility of an
engine failure when launching from our "short" 2600 foot runway. He
is very familiar with the airport. (Admitedly, off runway landing
sites are limited.)

Is it a common (and prudent) precaution to take an aerotow with a
motorglider if you have that option?

It's definitely not common, but sometimes is advisable. There are a
number of reasons to choose a tow:

- If the tow plane will give a markedly better climb at an airport with
limited emergency options (the one you mentioned)
- As long as the towplane can provide the same or better climb rate, you
have more margin because you don't have the drag of the extended engine
to deal with in an emergency
- You have all of your fuel to use for a retrieve, extending the flight,
or for the next day's flying (safari mode)
- Some motorgliders handle a cross-wind better when towed than when
self-launching
- in some (rare) situations, it's easier to integrate the motorgliders
with the towed gliders during the launch if everybody takes a tow

Personally, I've never thought it worth doing in the 500-600 flights
I've made.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

On Monday, August 26, 2013 10:38:05 AM UTC-7, Andrew wrote:
I found this website with an interesting commentary on motor

gliders.



http://www.trb.8m.com/index.html





Real has some important insights about the issues of flying MGs, but has reached a couple of very wrong conclusions.

First:

"The more complicated the motor the more dangerous. SLS is more problem than a sustainers, which in turns is more than an electric."

An self-launcher just has a larger motor than a sustainer; the complexity is very comparable. SLS will be heavier, which increases wing loading, but the start sequence is pretty much the same. In fact, I was surprised at the issue of getting all of the petal blades deployed - this is definitely not an issue with an SLS. Electrics are the clear winners on simplicity, but they are also the clear losers on range, which, flying 1000 k tasks over Nevada, is a big issue for me.

"Flying a motor glider could force you to more land out then having a pure glider."

If this actually happens, you are doing something seriously wrong. In Real's case this is his mystifying decision to carry ONLY 4 l of fuel. Fuel translates directly to range. If he had carried a full fuel tank he probably would not have had any landouts. The 13 l tank capacity only adds another 15 lbs of weight - this will have a negligible affect on wing loading (less than 2%).

The circumstances that give pure gliders a SLIGHT edge over MGs so emphasized by Real happens very rarely in reality. It happened to me a couple of times in 16 years. One was in a contest that had a weak day. I ended up landing at an airport (to get a landing card signed) and self-retrieved. Another pure glider also landed at the same airport. After I launched, a bystander asked the other pilot if he also was going to do the same thing! Not a single MG made it around that day w/o restarting, but pure gliders did (albeit by doing numerous low saves). I concluded that MGs were at a definite disadvantage in contests and stopped flying them.

Personally, I will only own an SLS (we don't have a tow plane here!). Pure glider owners must look at the short list of commercial operators and a few of the larger clubs if they want to tour the country - I only have to find an airport (of which there are 1000s)!

2G wrote, On 9/21/2013 9:04 AM:
Real has some important insights about the issues of flying MGs, but
has reached a couple of very wrong conclusions.

snip


"Flying a motor glider could force you to more land out then having a
pure glider."

If this actually happens, you are doing something seriously wrong.

I have to agree with Tom - this a really odd statement. Before I got my
motorglider, I'd land away from home about 3 or 4 times a year in my ASW
20 B; since getting my ASH 26 E 18 years ago, I've never had to land
away from except for one weather related situation. I've restarted in
the air over 160 times to avoid landing out. My wife thinks it's the
best glider we've ever had (it's my 5th one), because "it always gets back".

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

On Monday, August 26, 2013 1:38:05 PM UTC-4, Andrew wrote:
I found this website with an interesting commentary on motor
gliders.
http://www.trb.8m.com/index.html


Caution: Clicking on this link may infect your computer with a virus. My virus protection program (Avast) warned me that the site was spreading Infection: JS:Redirector-AJB [Trj]

If your virus protection program did not catch this, you might consider upgrading to Avast (I run the free version). On the other hand, this could be a false alarm.

son_of_flubber wrote, On 9/21/2013 10:21 AM:
On Monday, August 26, 2013 1:38:05 PM UTC-4, Andrew wrote:
I found this website with an interesting commentary on motor
gliders. http://www.trb.8m.com/index.html


Caution: Clicking on this link may infect your computer with a virus.
My virus protection program (Avast) warned me that the site was
spreading Infection: JS:Redirector-AJB [Trj]

If your virus protection program did not catch this, you might
consider upgrading to Avast (I run the free version). On the other
hand, this could be a false alarm.

Norton Internet Security on my Windows XP machine didn't find anything.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl