Flapless - where to turn base?

[pointer41]

Help me out on this one:

There are 2 schools of thought with flapless training, and I would like to gain your ideas. The 'traditional' flapless circuit will take a student further, to a 60 degree point for turning base, resulting in a flatter approach.

My preferred method uses a standard circuit pattern and standard 3.5 degree glidepath, for the following:
1) If you fly an ILS, the Glidepath cares beans if you have flaps or not, ergo you fly the standard glidepath.
2) Better visibility and more options on final, if Murphy ticks your engine.
3) Downside possibly, you have to manage your energy a bit better.

Your thoughts, por favor!

[Phenomenon]

The way I see it it remains personal preference. You are right, neither the localiser nor the glideslope knows or cares how much flaps you have or at what speed you're screaming in. That is all up to you.

Just keep in mind that with a cleaner aircraft you'll have a higher speed and lower power setting and a bigger turning circle for the same amount of bank. You can intentionally fly a flapless circuit just as you would a normal circuit, the turns will just be a little steeper and the ROD on the glideslope will be a little faster, but the angle will be the same.

Another reason why a flatter approach is advisable on a visual is because you'll have a quicker ROD and you'll lose more speed while arresting the ROD in the flare. On an ILS approach it doesn't make a difference cause the glideslope is fixed!

Back in the day my instructor told me, and this is true... an instructor can teach you how he flies a plane, but every pilot has his own preferences, so you'll develop you own way of flying with time.

[Tinstaafl]

Same approach as normal but less power (thrust) required due reduced drag. Some amount of reduced visibility over the nose but manageable. If you do otherwise does that mean you alter your approach profile & planform for every part-flap landing too?

[Rude Boy]

I'd say fly the same angle of approach regardless of flap setting. It leads to a reasonable level of consistency for all operations and keeps the proficiency level up for different conditions; eg flying a flat approach when flapless is one thing during the day, but who knows how flat is safe on a night approach, even when visual? You don't want to be practising different techniques in situations where you really do have better things to think about.

[low n' slow]

I agree. If this is SEP flying we're talking about, there's heaps of techniques for getting down safely without flaps. Slipping is one method I usually prefer and it can be adjusted to meet your needs precisely. S turns on final is also a good way to get a longer track to give you more time to descend within your standard pattern.

If we're talking SEP IFR or even MEP IFR, the time you break out at minima to touchdown is enought time to let you bleed of speed. Though not very comfortable for your passangers if you are carrying them, wingslipping works here aswell. Also, try wiggling the rudder. Basic glider theory is that the less control input you do, the more energy you save. Vice versa, by giving unecesary input in reasonable amount, will let you bleed of energy (but as I said, this is not comfortable to anyone in the plane and is not exactly covered in the CPL syllabus...). During my IFR training we would usually finish of the sessions with a "high speed ILS". No flaps and about 140 KIAS on final. No problems to get down with a long runway available to bleed of speed in the final segments of the approach. If you have a constant speed prop you can also use this to some extent, to aid in speed management.

In large planes, there's not a huge amount of options actually. Calculate with airspeed bleed of in the air and also on ground. Choose a loooong runway and be prepared to go off it at the DER. Alert the emergency services. Even if you don't go off the runway, the brake's will most likely get overheated and may require a fire truck to be on standby. My experience in the area of heavy jets is NIL though so I'll let someone with more knowledge comment on this.

/LnS

[Mark 1]

Training standardization has generally led to the extended downwind, add 5kts and use a 3 degree rather than the more usual 4 to 6 degree glide path.

But the same standardization usually means flaps are only selected after completing the base turn. So an actual flap failure will only be discovered after having positioned for a steeper approach. The choice then is glide or sideslip as required (sideslips are generally not popular with passengers) or go around.

I like sideslips; you'll probably get some static error on the ASI, but you can vary the amount precisely, and keep your usual descent profile.

Both techniques are valid, and shouldn't matter to an examiner, if flown correctly.