Glide slope not coming in

[Will W]

Thanks and I have tried your suggestions and they help, but how far away do you tell students to configure for landing. My instructor usually tells me to do that a bit before the FAF so that at FAF, I'm all configured and can call ATC and declare on final.

He also tells me that in IFR training, I'm not supposed to take any action that takes lift away, such as the speed break, because it hastens the descent rate... just wondering what are your thoughts about that one as well.

For ILS approaches in the case of vector to final, I teach to have flaps to take off position as the localizer is half way deflected and coming in. For the gear, I teach when the glideslope is half deflected from the top coming down, throw the gear. It will give the autopilot time to retrim so that all you do at glide slope intercept is pull the power back and descend down.

Something to remember and applies heavily to IFR flying is trim is moving the stability of the aircraft in reference to airspeed. Another way to say this is the plane wants to seek an airspeed based on trim. When you are level flight and trimmed for level flight, if you push over, you will speed up and the plane will on its own begin a climb "seeking" that airspeed.

Now apply this logic for approaches. When shooting the approach, the common thing new to IFR pilots do is they chase the glideslope by pulling or pushing the stick. Instead, have the plane trimmed for your approach speed before you intercept the glideslope to follow it down. When you reach the glide slope, pull the power back (about 12-16" MP in your aircraft depending on wind) and the use the power to get back on glideslope. Remember pitch for airspeed, power for altitude? You can treat an instrument approach the same way.

For non precision approaches VOR, Localizer, etc. approaches... As you get half deflection coming in on the radial/localizer, etc... Throw the flaps... 2 miles prior to the Final Approach Fix (FAF- point where you start your descent to minimums), put the gear out. It will give time for the autopilot, or you to retrim the aircraft for the desired speed in the new configuration.

Additionally, the autopilot will have no inpact on preventing the glideslope from showing up on an HSI. One has nothing to do with the other.

Speed brakes, assuming precise flight speed brakes, are certified for use in approach and landing and they even looked at how it would effect go around performance. It is not a limitation. Use them if you feel you need it. It shouldn't always be needed though except in the case where ATC told you to descend late and you need to slow down while your nose is down.

To get a side lobe signal from a glide slope, you would have to be crazy high above the real glide slope anyway and it is unlikely you'd make the mistake if you know we're you are on the approach. GTN 750/650 moving maps as well as Foreflight geo reference charts help keep that mental picture of where you are and where you should intercept it at.

Now go shoot some approaches and have some fun!

[M00N37]

On 5/31/2015 at 10:05 PM, Houman said:

Hi,

 

Continuing my IFR training and GS is now working ok, but my instructor is a bit surprised that even following the published approach altitude, the Glide Slope Is intermittent, it comes and then flag goes on, it helps a lot if I put takeoff flaps or even more to change the angle, but changes a bit my approach settings to be 4 or 5 miles out and put on flaps.

 

So what I have done in today's exercise is to start the approach as non-precision and not rely on the intermittent GS until approaching the FAF and slowing down, brining down the gear and flaps and the GS comes in and stays in no problem what to so ever.

 

So my question is how does other more IFR experiences pilots do with GS reception in a Mooney beside the Flaps. My CFI tells me this is the 1st time he has seen this, he usually gives IFR training in a Beech Twin.

 

Thanks !

 

I have the exact same issue as you. Glideslop wouldn’t work unless I lower gear and flap.

I tested by briefly pull the nose up while tracking glideslope and flag came on immediately. 

Is it equipment malfunction or this is how the plane needs to be flown ? 

[carusoam]

That sounds a bit sub optimal to me...

Since the discussion is all about eclipsing the antenna with various parts of the plane...

It may be possible that the signal strength isn’t quite as high as it should be... something is getting lost between the antenna and the receiver...

 

Sure it should be optimized for the configuration you use the most... but if you get a flag in IMC because you change configuration... that can’t be a good way to continue...

Can you have your radio shop check the antenna and wiring connections for proper signal strength?

PP thoughts only, not a radio expert...

Best regards,

-a-