Decision making process - TWICQ

# Introduction

During any abnormal or emergency phase of flight, pilots’ judgement and actions are seen as critical inputs to ensure the safety of the flight. In some cases the situation can become very complex, especially when operating under IFR (Instrument Flight Rules) or at night time. With limited or no visual reference and undesired aircraft state, pilots are often easy to get stressed and over loaded, which may lead them to rush through the decision making process and come up with an immature conclusion.

A correct decision-making process model would help pilot to gather all the useful information that is required and obtain a good situational awareness before making any decisions. A decision making model called TWICQ is developed at Massey, all the students are required to carry out this decision making process on the completion of memory items during any abnormal or emergency situation. The TWICQ process includes:

• Terrain
• Weather
• Intensions
• Control
• QRH

Described below is an expanded series of questions that a pilot may ask depends on the phase of flight. Questions are used to satisfy pilots that an item is considered, action is taken, planning is made for the unfolding of the checklists at an appropriate time and place to ensure the arrival safety on a suitable runway. The question format is to aid learning, when competence is reached the pilot would make a statement. This is by example only and must be tailored to the particular situation.

# Terrain

## Departure phase

Are you above the profile for departure, or the miss approach?

3.3% does not mean much in an emergency when the brain is loaded up. The rate of climb calculated for a departure can be misleading when affected by a tail wind. A simple formula can be used to calculate the altitude is required on departure.

Feet per nm (nautical mile) x distance eg. 200’ per nm. At 3 DME what altitude should we be?

## Enroute clime phase

Are we above MSA (Minimum Safe Altitude)?
Are we going to get MSA?
What are the DME steps?

## Enroute cruise phase

Can we maintain altitude?
Can we stay above MSA?
Drift down rates?
Where is the high terrain relative to our position?
Have we crossed, or are we yet to cross, the terrain that determines MSA for this track?

## Approach & Arrival phase

Am I above any minimum altitude?
Can I stay above them?
Am I on the Approach Profile?

On a clam day one would simply look at the plate for the final approach step heights relating to the particular DME. On a turbulent day asymmetric all the pilots concentrated motor skills on flying the aircraft to maintain blue line (single engine climb speed). Therefore as with the departure we have a simple formula to assist quick checks of the approach profile the formula is:
3 x DME and add two zeros to convert to altitude
eg. At 7 nm, the altitude should be at is 3 x 7 =21, therefore 2100 ft

The approach brief should include the profile adjustment for altitude or conditions. On a normal approach on a calm day if the profile altitude at 7 DME is 1900 ft then the brief should include the statement “I will fly 3x profile less 200 ft. Alternatively if it is a very low cloud base and getting visual is doubtful one can fly a 3x profile on this approach intending to get to MDA earlier provided the 3x profile, (flying 200’ low on advisories), dose not break any minimum altitude on the approach. Lastly if one is asymmetric on approach, conditions are turbulent and the prospect of maintaining the profile is doubtful one might add 200’ on the normal profile so the statement in the brief would be “non normal approach I will fly a 3x profile plus 200 ft.”

# Weather

## Departure phase

Confirmation of – departure, destination, alternate, secondary options, enroute
This will be easier with a support pilot, the PIC (Pilot in Command) could ask them to go away and get the weather. In a single pilot crew scenario writing down extensive weather information on after an EFATO (Engine Failure After Takeoff) is not advisable. This weather check is a brief update or confirmation of conditions already understood by the pilot to confirm nothing has got worse to below minima or improved significantly now opening an option that was now available before departure.
This expected statement might be “Departure … is below landing minima, I will continue to my departure alternate.” With a support pilot the request would be “ confirm the weather”. The support pilot will have been briefed prior to the departure what weather effected decision making points on the departure, so would know check departure and departure alternate, and maybe one other option, to confirm weather from control.

## Enroute phase

Is the weather ahead as expected, better or worse?
Have I got reported cloud base, visibility, wind strength and direction?
Is it better somewhere else?

## Approach phase

What is the condition like at destination?
Is the weather condition at destination above landing minima?
Am I likely to get visual on the approach or should I continue on the instrument approach?

# Intensions

What are you going to do?
Where are you going to go?
How are you going to get there?

The input from the support pilot might often be helpful. PIC (Pilot In Command) should always consider the input from the support pilot and encourage him/her to speak up. By taking account of all possible solutions, both pilots should evaluate them together and come up with an agreed conclusion. The expected statement might be, “Before I divert I will enter the hold and take another look at the weather condition.”

# Control

Contact ATC (Air Traffic control) and declare emergency?
Inform them of intension
Seek information and assistance
When time is available, notify base and ask for any further assistance if required.
Carry out the plan, continue to review to ensure you are always in the best possible position given the circumstances. Review as new information comes to hand, or any time a significant factor is confirmed different to that briefed or expected.

# QRH

Decide when you are going to action this;
now, later, in a hold, when clear of terrain, in the cruise?

# Recommendation

The above decision-making model is helpful in gathering all the useful information and assist pilots to make a good decision in the unlikely event of emergency. However, this model should not limit the factors that are taken to consider by pilots as every scenario varies largely on its surrounding environment. In order to obtain a high level of situational awareness, pilots must keep an open mind to the external and internal factors. Good decisions can only be made when the pilots have an open mind, a positive attitude, a good situational awareness and constantly re-evaluate the decisions that they have made.

Reference:
Massey University School of Aviation (November 2010). Pilots Standard Operating Procedures
Massey University School of Aviation (February 2010). Crew Resource Management Handbook

page revision: 0, last edited: 17 Sep 2011 02:33