IFR Skill-Building: How To Hold A Glide Slope
Introduction
Today is another IFR skill-building day with Anita. She's new to instrument flying and just transitioning from the enroute environment to navigating Airways to the approach environment. Today, we're working on 500-foot per minute descents at 90 knots, a critical skill for flying a glide slope or a glide path.
Preparing for the Descent
Before starting the descent, we adjust our heading to zero six zero, with a slight left turn. This ensures we are properly aligned for the descent.
As we prepare for the descent, Anita is reminded to remember the steps involved in descending and to talk through them. It's important to factor in the desired airspeed of 90 knots. So, she needs to slow down the aircraft by reducing the power and holding the pitch until she reaches the target airspeed.
Instrument flying, just like visual flying, requires setting sight pictures and verifying performance. In this case, our goal is to maintain an airspeed of 90 knots and a descent rate of 500 feet per minute.
Once the aircraft is slowed down, Anita gently lets the nose fall to establish a new sight picture and verifies that she is achieving the desired descent rate on the vertical speed indicator (VSI).
Instrument flying relies on pitch control to manage vertical speed and power control to manage airspeed. The focus is on pitching to maintain a descent rate of 500 feet per minute and powering to maintain an airspeed of 90 knots.
Throughout the descent, Anita adjusts the pitch and power to maintain the desired performance. She finds that pitch control is sensitive, but with practice, she becomes more adept at catching the target descent rate of 500 feet per minute.
Working with ILS Needles
Next, we introduce the use of Instrument Landing System (ILS) needles to provide course guidance during the descent. Anita is instructed to add the ILS needles to her instrument panel display and observe how her performance aligns with the guidance provided.
As we approach the final approach fix for Oakland's runway 28R, Anita focuses on the ILS needle and adjusts her descent accordingly. The key is to power back to maintain an airspeed of 90 knots and pitch down to maintain a descent rate of 500 feet per minute.
By monitoring the ILS needle, Anita can ensure that she stays on track and maintains the desired glide slope. The ILS needles serve as a visual confirmation of her performance during the approach.
Mastering the Descent
Knowing what to expect and having a clear plan in mind is crucial in flying. Understanding the power setting required for a 500-foot per minute descent ahead of time greatly helps achieve a smooth and controlled descent.
Although the specific power setting may vary, being familiar with the approximate power setting for most light airplanes can provide a good starting point. In this case, a power setting of 5 is used as a protip.
Throughout the descent, Anita focuses on flying the aircraft and cross-checking her instruments. She aims for small sight pictures and continually measures her performance to ensure she is maintaining the desired airspeed and descent rate.
By following these steps and using the ILS needles as a reference, Anita successfully completes her first ILS approach with ease. This exercise demonstrates the effectiveness of the 500-foot per minute descent technique in maintaining a glide slope.
Conclusion
Mastering the skill of executing a 500-foot per minute descent at 90 knots is crucial for instrument flying. It requires precision in pitch and power control, as well as a thorough understanding of instrument indications.
Anita's successful demonstration of this skill highlights the importance of practice and familiarity with the aircraft's performance characteristics. By consistently aiming for the desired airspeed and descent rate, pilots can confidently navigate a glide slope or glide path during instrument approaches.
Remember to always be prepared, know your power settings, and understand the sight pictures required for different phases of flight. With practice and experience, you too can become proficient in executing 500-foot per minute descents and other essential instrument flying techniques.