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shumway76
17th Apr 2013, 02:20
During my PPL training I was trained under the old "RAF" 'syllabus'.

In VFR navigation we were taught to not only draw the lines joining the reporting points, but also beside each of these lines we drew a 'doghouse', with a triangle roof which is written the heading, then under the roof is 3 rectangular boxes, making it look like a 3 storey house with a triangle roof.

For those who used this technique, pls help me out. What were the e info you filled up in the 3 rectangle boxes? Was it cruise altitude, safety altitude & EET? If yes, in which order?

Can't seem to find any info on this in the PPL nav books.

Cheers!

tmmorris
17th Apr 2013, 11:12
I was taught this but not by the RAF. It was

Triangle: as you say, heading
EET
Planned altitude
MSA

I did the last two in full (e.g. 3500, 1700) though 35 and 17 might be simpler.

Tim

shumway76
18th Apr 2013, 06:47
Thanks tmmorris!

I wonder why there is no mention of this in the CAA PPL books. It only mentions to draw the route lines & timing on your chart, no mention on the dog house.

A and C
18th Apr 2013, 08:05
I think that the doghouse is most usefull in a high workload situation, I don't discount it for any type of flying and don't use it myself on a normal basis as I just use a paper flight log.

The situation that requires this type of preparation is for low level precision navigation where you are going to spend 99.9 % of your time with your head out of the cockpit with the occasional glance inside for a systems check and bringing the map up to almost windscreen level to check it.

Also see this video !

YouTube (http://m.youtube.com/#/watch?v=NQWZEVaoFKQ&desktop_uri=%2Fwatch%3Fv%3DNQWZEVaoFKQ)

Tim should be able to tell you the location of the crossroad & railway in the opening few mins as it is very near his base.

Mariner9
18th Apr 2013, 09:33
3 things to put in the boxes?

Use

a

GPS

This should provoke a debate :ok:

G-F0RC3
18th Apr 2013, 10:42
3 things to put in the boxes?
Use
a
GPS
This should provoke a debate

I use a GPS, but I always have a back-up manually-produced plan in place in case it fails. Any other way is taking a silly risk imo.

I find the dog-house system at each reporting point to be a bit convoluted though. Drawing it shrouds detail on the chart that I don't want to be obscured.

A819
18th Apr 2013, 13:28
Heading
Track
Altitude

Then times in mins from start on leg go next to fix/turning points

riverrock83
18th Apr 2013, 14:52
I get the impression there are lots of slight varients of this...

I've been taught heading (in the roof)
Planned Altitude
Height

Planned altitude should be above MSA - if you are below MSA then you should have eyes out VFR anyway...

Don't know why putting the track on is useful, unless you weren't using a paper plog backup - so all your planning is on the map?.

znww5
18th Apr 2013, 15:30
Looking at the Vigilant TMG training manual, the doghouse is just part of the 'fly off the map' approach used by the VGS.

They use 1/4 mill charts and mark the following on it: start point, fixes, turning points, doghouse (Mag heading, mag track, leg altitude), clock marks and fuel circles (fuel remaining and fuel required to divert with reserve).

That all slots in with the use of MDR for calculatng drift, groundspeed etc.

Whopity
18th Apr 2013, 16:43
Frankly, what you put in the Doghouse is up to you, what information do you need? It was a system used in the fast jet World and is not very relevant to light aircraft operation. I was not aware the CAA had produced any books on PPL navigation, its never been their job to do so.

Drawing great big boxes near turning points is unnecessary clutter on the chart and more likely to cover up something you might want to see than provide any useful information. Track and Time is all you really need.

overandout
18th Apr 2013, 17:32
Low level (1000 FT AGL), VFR for accurate nav all info on the map .No plog required.
Triangle as you say for Track (M). Marks on map at every minute at required Ground speed. Required ETA in Mins and secs written on at each Turning point. All nav by look out and map. No Heading needed to be pre-calculated. If drifting a couple of hundred yards of track adjust to follow track exactly. Adjust speed to keep to minute marks and hence required ETA.

As video originally by RAF ; now used in Precision and Rally Flying Competitions every week througout Europe.
Not difficult and a sociable way of improving accurate flying.
http://www.precisionflying.co.uk/

Have fun
Overandout

BEagle
18th Apr 2013, 17:50
Well, RAF Learning Command might have used the 'doghouse', but not the general RAF.

All I used on the Hunter / Buccaneer / Vulcan / Hawk / F-4 / Bulldog was the magnetic heading at the leg start (or magnetic track if the W/V was unknown / not significant), timing marks at the calculated groundspeed and times at fix points / turning points. However, Safety Altitude was marked in Big Red Numbers in an unique part of the map.

You need minimum detail to be able to fly the leg, don't obscure detail, K.I.S.S and be prepared for the GPS to go 'tango uniform' at the wrong moment!

foxmoth
18th Apr 2013, 17:58
Well a couple of bits here where people do not know how to do things:-

I find the dog-house system at each reporting point to be a bit convoluted though. Drawing it shrouds detail on the chart that I don't want to be obscured.. If it shrouds detail then you are drawing it too close to track! An inch or so away is 10 miles on a half mil - if you need detail that far out there is something wrong!

Planned altitude should be above MSA - if you are below MSA then you should have eyes out VFR anyway...

Why should it be above MSA? This is VFR nav, you might have a 3000' mast 5 miles off track, but does not mean you cannot plan to fly at 2,500, yes eyes should be outside, but to navigate you still need to look inside at times, can be at a GPS or a map, but if a map you want to have it marked so you can look down and see the important info at a glance, and this is where the doghouse can help. MSA needs to be marked down and known, but this is to climb to if you cannot keep VFR, not necessarily what you plan to.

Pilot.Lyons
18th Apr 2013, 21:09
Lol mariner9